40 Commits

Author SHA1 Message Date
Michael Roitzsch
9542568442 internals: update for macOS 13.2 Ventura 2022-12-26 18:33:03 +01:00
Michael Roitzsch
05eed46555 flake: update for Xcode 14.2 2022-12-26 10:02:28 +01:00
Michael Roitzsch
72af1896ec flake: update for Xcode 14.1 2022-11-06 20:37:58 +01:00
Michael Roitzsch
40b2576d55 internals: update for macOS 12.4 Monterey 2022-06-06 21:45:17 +02:00
Michael Roitzsch
909ec8a160 flake: update for Xcode 13.4 2022-05-25 18:45:24 +02:00
Michael Roitzsch
b92ed8e175 internals: update for macOS 12.3 Monterey 2022-03-25 08:20:11 +01:00
Michael Roitzsch
e33fabd772 flake: update for Xcode 13.3 2022-03-25 08:19:46 +01:00
Michael Roitzsch
b494b38956 flake: update for Xcode 13.2 2022-01-02 15:02:24 +01:00
Michael Roitzsch
8d62d3e215 formally conform to the TSV file format
• move internals.txt to internals.tsv (bonus: GitHub built-in rendering)
• add a header in the first line
• ignore first line for sort checking
• ignore first line for HTML rendering
2022-01-02 15:02:24 +01:00
Michael Roitzsch
5e92d0e636 internals: update for macOS 12.1 Monterey 2021-11-22 14:11:48 +01:00
Michael Roitzsch
33947b2f46 Makefile: test for tool build errors 2021-11-08 10:44:59 +01:00
Michael Roitzsch
81f318f1e1 flake: fix acextract build (again) 2021-11-08 10:38:11 +01:00
Michael Roitzsch
07288c72e1 flake: update Xcode version 2021-11-08 10:37:33 +01:00
Michael Roitzsch
f3150df424 Makefile: fix entitlements export for Monterey 2021-10-29 19:52:30 +02:00
Michael Roitzsch
ef992d99d1 flake: enable snapshot reverting
snapUtil -r
2021-10-25 12:04:53 +02:00
Michael Roitzsch
28560df58f flake: fix Swift compiler crash 2021-10-25 12:03:31 +02:00
Michael Roitzsch
31fcb59c80 Makefile: extract DriverKit dyld cache 2021-10-25 12:03:31 +02:00
Michael Roitzsch
2deea7c208 flake: Monterey-compatible dyld cache extractor 2021-10-25 12:03:12 +02:00
Michael Roitzsch
563347a6db Makefile: assume a flake-capable Nix is installed 2021-10-20 10:43:55 +02:00
Michael Roitzsch
345d5a24c0 Makefile: configurable Xcode installation 2021-10-20 10:43:55 +02:00
Michael Roitzsch
40216ef6d4 flake: use unstable branch of nixpkgs 2021-10-20 10:43:55 +02:00
Michael Roitzsch
f79226a965 flake: use attribute naming convention, add lock 2021-10-20 10:43:55 +02:00
Michael Roitzsch
2cec40761a internals: update for macOS 11.4 2021-05-25 10:32:25 +02:00
Michael Roitzsch
1036b6326c Makefile: renew database if current system is newer 2021-05-25 10:31:22 +02:00
Michael Roitzsch
cfd54c9d8c flake: update to Xcode 12.5 2021-04-28 10:52:32 +02:00
Michael Roitzsch
30bdc30392 internals: update for macOS 11.3 2021-04-24 14:22:02 +02:00
Michael Roitzsch
aeae2a6157 Makefile: use most current compressed database 2021-04-24 14:21:31 +02:00
Michael Roitzsch
73de585019 flake: unquoted URLs are deprecated 2021-03-30 21:24:32 +02:00
Michael Roitzsch
9dfebf24ff internals: update with February 2021 security info 2021-03-28 10:00:00 +02:00
Michael Roitzsch
924e53e9b6 Makefile: tolerate errors with interactive SQlite 2021-03-27 16:01:19 +01:00
Michael Roitzsch
7ad7ac85f2 improve interactive SQLite completions
rename index to avoid it having the same prefix as the files table
2021-03-24 19:52:38 +01:00
Michael Roitzsch
b84e3ba5cf clear extended attributes 2021-03-24 18:07:00 +01:00
Michael Roitzsch
eaba592bcc handle URL fragment as search term
allows direct linking to specific searches
2021-03-11 10:02:40 +01:00
Michael Roitzsch
c26b374f48 update Xcode and fix crash in snapUtil 2021-02-22 09:37:29 +01:00
Michael Roitzsch
7bfdb02cc9 add a textual database dump of most relevant info
useful for diffing databases of multiple OS versions against each other
2020-12-31 18:41:47 +01:00
Michael Roitzsch
320cee87e0 fix passing DB as command line variable 2020-12-31 18:12:51 +01:00
Michael Roitzsch
23f5c368e0 better Nix flakes documentation link 2020-12-31 17:26:04 +01:00
Michael Roitzsch
f85006a1c9 convenience target for interactive database access 2020-12-31 17:25:47 +01:00
Michael Roitzsch
2128e5251f update to Xcode 12.3 2020-12-31 17:25:21 +01:00
Michael Roitzsch
6306ad242c document SQLite database and internals check 2020-11-24 19:37:06 +01:00
6 changed files with 426 additions and 188 deletions

View File

@@ -1,16 +1,18 @@
override DB := $(if $(DB),$(DB:.lz=),$(lastword $(sort internals-$(shell sw_vers -productVersion).db $(basename $(wildcard internals-*)))))
MY_INTERNALS = $(HOME)/Library/Mobile\ Documents/com~apple~TextEdit/Documents/Apple\ Internals.rtf
DB := $(if $(DB),$(DB:.lz=),internals-$(shell sw_vers -productVersion).db)
DB_TARGETS = db_files db_binaries db_manifests db_assets db_services
CHECK_TARGETS = check_files check_binaries check_manifests check_services
.PHONY: all check $(DB_TARGETS) $(CHECK_TARGETS)
.PHONY: all check view sqlite $(DB_TARGETS) $(CHECK_TARGETS)
.INTERMEDIATE: $(DB)
all: $(DB).lz check
ifneq ($(wildcard $(MY_INTERNALS)),)
internals.txt: $(MY_INTERNALS)
textutil -cat txt "$<" -output $@
internals.tsv: $(MY_INTERNALS)
printf 'Term\tDescription\n' > $@
textutil -cat txt $@ "$<" -output $@
xattr -c $@
endif
ifneq ($(wildcard $(DB).lz),)
@@ -26,41 +28,60 @@ $(DB).lz: $(DB)
rm -rf dyld
endif
check: internals.txt
@LANG=en sort --ignore-case $< | diff -uw $< -
check: internals.tsv
@(head --lines=1 ; LANG=en sort --ignore-case) < $< | diff -uw $< -
@$(MAKE) --silent --jobs=1 $(CHECK_TARGETS)
define VIEW
SELECT path,os FROM files;
SELECT path,os,name FROM files NATURAL JOIN assets;
SELECT path,os,dylib FROM files NATURAL JOIN linkages;
SELECT files.path,os,key,value FROM files NATURAL JOIN services, json_each(plist);
SELECT files.path,os,key,value FROM files NATURAL JOIN entitlements, json_each(plist);
endef
export VIEW
view: $(DB)
echo "$$VIEW" | sqlite3 -bail $< | LC_COLLATE=C sort
sqlite: $(DB)
sqlite3 $< || true
# MARK: - data extraction helpers
NIX = $(shell nix-build --no-out-link -A nixFlakes '<nixpkgs>')/bin/nix
ACEXTRACT = $(shell \
$(NIX) --experimental-features 'nix-command flakes' build --no-write-lock-file .\#acextract && \
ACEXTRACT = $(shell nix build --no-write-lock-file .\#acextract && \
readlink result && rm result)/bin/acextract
DSCU = $(shell \
$(NIX) --experimental-features 'nix-command flakes' build --no-write-lock-file .\#dyld-shared-cache && \
readlink result && rm result)/bin/dyld_shared_cache_util
DSCEXTRACTOR = $(shell nix build --no-write-lock-file .\#dsc-extractor && \
readlink result && rm result)/bin/dyld-shared-cache-extractor
dyld: /System/Library/dyld/dyld_shared_cache_$(shell uname -m)
$(DSCU) -extract $@ $<
dyld: /System/Cryptexes/OS/System/Library/dyld/dyld_shared_cache_x86_64h /System/Cryptexes/OS/System/DriverKit/System/Library/dyld/dyld_shared_cache_x86_64h
if ! test -x $(DSCEXTRACTOR) ; then \
printf '\033[1mdscextractor tool unavailable\033[m\n' >&2 ; \
echo 'FAIL;' ; \
exit 1 ; \
fi
for i in $+ ; do $(DSCEXTRACTOR) $$i $@ ; done > /dev/null
find $@ -type f -print0 | xargs -0 chmod a+x
XCODE = $(lastword $(wildcard /Applications/Xcode.app /Applications/Xcode-beta.app))
prefix = $$(case $(1) in \
(macOS) ;; \
(macOS-dyld) echo $(dir $(realpath $(firstword $(MAKEFILE_LIST))))/dyld ;; \
(iOS) echo /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Library/Developer/CoreSimulator/Profiles/Runtimes/iOS.simruntime/Contents/Resources/RuntimeRoot ;; \
(tvOS) echo /Applications/Xcode.app/Contents/Developer/Platforms/AppleTVOS.platform/Library/Developer/CoreSimulator/Profiles/Runtimes/tvOS.simruntime/Contents/Resources/RuntimeRoot ;; \
(watchOS) echo /Applications/Xcode.app/Contents/Developer/Platforms/WatchOS.platform/Library/Developer/CoreSimulator/Profiles/Runtimes/watchOS.simruntime/Contents/Resources/RuntimeRoot ;; \
(iOS) echo $(XCODE)/Contents/Developer/Platforms/iPhoneOS.platform/Library/Developer/CoreSimulator/Profiles/Runtimes/iOS.simruntime/Contents/Resources/RuntimeRoot ;; \
(tvOS) echo /Library/Developer/CoreSimulator/Volumes/tvOS_*/Library/Developer/CoreSimulator/Profiles/Runtimes/tvOS*.simruntime/Contents/Resources/RuntimeRoot ;; \
(watchOS) echo /Library/Developer/CoreSimulator/Volumes/watchOS_*/Library/Developer/CoreSimulator/Profiles/Runtimes/watchOS*.simruntime/Contents/Resources/RuntimeRoot ;; \
esac)
find = \
{ \
$(2) find /Library /System /bin /dev /private /sbin /usr ! \( -path /System/Volumes/Data -prune \) $(1) 2> /dev/null | sed 's/^/macOS /' ; \
cd /Applications/Xcode.app/Contents/Developer ; find Library Toolchains Tools usr $(1) | sed 's|^|macOS /Applications/Xcode.app/Contents/Developer/|' ; \
$(2) find /Library /System /bin /dev /private /sbin /usr ! \( -path /Library/Developer/CoreSimulator/Volumes -prune \) ! \( -path /System/Volumes/Data -prune \) $(1) 2> /dev/null | sed 's/^/macOS /' ; \
cd $(XCODE)/Contents/Developer ; find Library Toolchains Tools usr $(1) | sed 's|^|macOS /Applications/Xcode.app/Contents/Developer/|' ; \
test -d "$(call prefix,macOS-dyld)" && cd "$(call prefix,macOS-dyld)" && find . $(1) | sed '1d;s/^\./macOS-dyld /' ; \
cd $(call prefix,iOS) ; find . $(1) | sed '1d;s/^\./iOS /' ; \
cd $(call prefix,tvOS) ; find . $(1) | sed '1d;s/^\./tvOS /' ; \
cd $(call prefix,watchOS) ; find . $(1) | sed '1d;s/^\./watchOS /' ; \
cd "$(call prefix,iOS)" ; find . $(1) | sed '1d;s/^\./iOS /' ; \
cd "$(call prefix,tvOS)" ; find . $(1) | sed '1d;s/^\./tvOS /' ; \
cd "$(call prefix,watchOS)" ; find . $(1) | sed '1d;s/^\./watchOS /' ; \
}
file = SELECT id, $(1) FROM files WHERE os = '$$os' AND path = '$$(echo "$$path" | sed "s/'/''/g")'
@@ -83,7 +104,7 @@ db_files:: dyld
echo 'CREATE TABLE files (id INTEGER PRIMARY KEY, os TEXT, path TEXT, executable BOOLEAN);'
$(call find,,sudo) | sed -E "s/'/''/g;s/([^ ]*) (.*)/INSERT INTO files (os, path) VALUES('\1', '\2');/"
find $(HOME)/Library | sed "s|^$(HOME)|~|;s/'/''/g;s/.*/INSERT INTO files (os, path) VALUES('macOS', '&');/"
echo 'CREATE INDEX files_path ON files (path);'
echo 'CREATE INDEX _files_path ON files (path);'
db_binaries:: dyld
printf '\033[1mcollecting executable information...\033[m\n' >&2
@@ -98,8 +119,8 @@ db_binaries:: dyld
if test -r "$(call prefix,$$os)$$path" && file --no-dereference --brief --mime-type "$(call prefix,$$os)$$path" | grep -Fq application/x-mach-binary ; then \
objdump --macho --dylibs-used "$(call prefix,$$os)$$path" | \
sed "1d;s/^.//;s/ ([^)]*)$$//;s/'/''/g;s|.*|INSERT INTO linkages $(call file,'&');|" ; \
codesign --display --entitlements - "$(call prefix,$$os)$$path" 2> /dev/null | \
sed 1d | plutil -convert json - -o - | \
codesign --display --xml --entitlements - "$(call prefix,$$os)$$path" 2> /dev/null | \
plutil -convert json - -o - | \
sed "/^<stdin>: Property List error/d;/^{}/d;s/'/''/g;s|.*|INSERT INTO entitlements $(call file,json('&'));\n|" ; \
strings -n 8 "$(call prefix,$$os)$$path" | \
LANG=C sed "s/'/''/g;s|.*|INSERT INTO strings $(call file,'&');|" ; \
@@ -116,6 +137,11 @@ db_manifests::
done
db_assets::
if ! test -x $(ACEXTRACT) ; then \
printf '\033[1macextract tool unavailable\033[m\n' >&2 ; \
echo 'FAIL;' ; \
exit 1 ; \
fi
printf '\033[1mcollecting asset catalog information...\033[m\n' >&2
echo 'DROP TABLE IF EXISTS assets;'
echo 'CREATE TABLE assets (id INTEGER REFERENCES files, name TEXT);'
@@ -138,15 +164,15 @@ $(DB_TARGETS)::
echo 'COMMIT TRANSACTION;'
# MARK: - check targets for internals.txt
# MARK: - check targets for internals.tsv
check_files: internals.txt $(DB)
check_files: internals.tsv $(DB)
printf '\033[1mchecking files...\033[m\n' >&2
grep -ow '~\?/[^,;]*' $< | sed -E 's/ \(.*\)$$//;s/^\/(etc|var)\//\/private&/' | \
sed "s/'/''/g;s|.*|SELECT count(*), '&' FROM files WHERE path GLOB '&';|" | \
sqlite3 $(DB) | sed -n "/^0|/{s/^0|//;p;}"
check_binaries: internals.txt $(DB)
check_binaries: internals.tsv $(DB)
printf '\033[1mchecking command line tools...\033[m\n' >&2
grep -o 'command line tools\?: [^;]*' $< | sed 's/^[^:]*: //;s/ //g;s/([^)]*)//g' | tr , '\n' | \
sed "s/'/''/g;s|.*|SELECT count(*), '&' FROM files WHERE executable = true AND path GLOB '*/&';|" | \
@@ -160,13 +186,13 @@ check_binaries: internals.txt $(DB)
sed "s/'/''/g;s/.*/SELECT count(*), '&' FROM strings WHERE string GLOB '*&*';/" | \
sqlite3 $(DB) | sed -n "/^0|/{s/^0|//;p;}"
check_manifests: internals.txt $(DB)
check_manifests: internals.tsv $(DB)
printf '\033[1mchecking extension points...\033[m\n' >&2
grep -o 'extension points\?: [^;]*' $< | sed 's/^[^:]*: //;s/ //g;s/([^)]*)//g' | tr , '\n' | \
sed "s/'/''/g;s|.*|SELECT count(*), '&' FROM info, json_each(plist, '$$.NSExtension') WHERE key = 'NSExtensionPointIdentifier' AND value = '&';|" | \
sqlite3 $(DB) | sed -n "/^0|/{s/^0|//;p;}"
check_services: internals.txt $(DB)
check_services: internals.tsv $(DB)
printf '\033[1mchecking launchd services...\033[m\n' >&2
grep -o 'launchd services\?: [^;]*' $< | sed 's/^[^:]*: //;s/ //g;s/([^)]*)//g' | tr , '\n' | \
sed "s/'/''/g;s|.*|SELECT count(*), '&' FROM services, json_each(plist) WHERE key = 'Label' AND value = '&';|" | \

View File

@@ -4,8 +4,8 @@ Apple Internals
This repository provides tools and information to help understand and analyze the internals
of Apples operating system platforms. Information is collected in a text file and
[presented on a website](https://mroi.github.io/apple-internals). A [Nix
flake](https://github.com/tweag/rfcs/blob/flakes/rfcs/0049-flakes.md) allows to build the
following externally hosted tools:
flake](https://nixos.wiki/wiki/Flakes) allows to build the following externally hosted
tools:
[**acextract**](https://github.com/bartoszj/acextract)
Unpacks asset catalogs to individual files.
@@ -16,6 +16,16 @@ Extracts dynamic libraries from the dyld linker cache.
[**snapUtil**](https://github.com/ahl/apfs)
Manages APFS snapshots.
The Makefile aggregates various kinds of information from the system in a SQLite database
and checks the internals text file against this information. Collected details include:
* all file names of the installed macOS and the iOS, tvOS, and watchOS simulators
* linkages of binaries to libraries
* entitlements for all executables
* plain-text strings embedded in binaries
* launchd service descriptions and bundle Info.plist content
* lists of assets inside asset catalogs
___
This work is licensed under the [MIT license](https://mit-license.org) so you can freely use
and share as long as you retain the copyright notice and license text.

106
flake.lock generated Normal file
View File

@@ -0,0 +1,106 @@
{
"nodes": {
"acextract": {
"flake": false,
"locked": {
"lastModified": 1556467432,
"narHash": "sha256-Yh437j5HLwh+s2qBKo3YruBHSJxqH142LuM/Unf+rV4=",
"owner": "bartoszj",
"repo": "acextract",
"rev": "df3b018d53cd4b684a5f6d63535dcc4156be1a97",
"type": "github"
},
"original": {
"owner": "bartoszj",
"repo": "acextract",
"type": "github"
}
},
"command-line": {
"flake": false,
"locked": {
"lastModified": 1556260068,
"narHash": "sha256-3BvUfIbbSsv8AHeg+nEjGVNDbgSOf/P7l6EFo+DvE/I=",
"owner": "iHTCboy",
"repo": "CommandLine",
"rev": "b8209dc17ac1dd0f97ebfbd6a77a0633552626ca",
"type": "github"
},
"original": {
"owner": "iHTCboy",
"repo": "CommandLine",
"type": "github"
}
},
"dsc-extractor": {
"flake": false,
"locked": {
"lastModified": 1662651226,
"narHash": "sha256-pI9pP5QhO1X2hdJTxVl8p1xp+bDJzzfCsVNebDUTd0o=",
"owner": "keith",
"repo": "dyld-shared-cache-extractor",
"rev": "c9da45a40a70d9fc0d1c955190b9efb685e55cf6",
"type": "github"
},
"original": {
"owner": "keith",
"repo": "dyld-shared-cache-extractor",
"type": "github"
}
},
"nixpkgs": {
"locked": {
"lastModified": 1671936867,
"narHash": "sha256-tOok3/MJWoRUEoPU5Ma/cTCeuw8ACx3Ozu1MlFcdvc8=",
"owner": "NixOS",
"repo": "nixpkgs",
"rev": "18ee49839ea8817218c3bfe3a62e06f47a10fdd5",
"type": "github"
},
"original": {
"id": "nixpkgs",
"type": "indirect"
}
},
"root": {
"inputs": {
"acextract": "acextract",
"command-line": "command-line",
"dsc-extractor": "dsc-extractor",
"nixpkgs": "nixpkgs",
"snap-util": "snap-util",
"snapshot-header": "snapshot-header"
}
},
"snap-util": {
"flake": false,
"locked": {
"lastModified": 1647211082,
"narHash": "sha256-zQ/0Cpo6CCeKXafeERjBCQ2gv9396c7UZU+VmViQVIc=",
"owner": "ahl",
"repo": "apfs",
"rev": "2bcf604966949f618e6a6ce33ca8ae1721494e6d",
"type": "github"
},
"original": {
"owner": "ahl",
"repo": "apfs",
"type": "github"
}
},
"snapshot-header": {
"flake": false,
"locked": {
"narHash": "sha256-/2aR6n5CbUobwbxkrGqBOAhCZLwDdIsoIOcpALhAUF8=",
"type": "tarball",
"url": "https://github.com/apple/darwin-xnu/archive/refs/tags/xnu-6153.141.1.tar.gz"
},
"original": {
"type": "tarball",
"url": "https://github.com/apple/darwin-xnu/archive/refs/tags/xnu-6153.141.1.tar.gz"
}
}
},
"root": "root",
"version": 7
}

187
flake.nix
View File

@@ -2,98 +2,127 @@
description = "tools to understand the internals of Apples operating systems";
inputs = {
acextract = {
url = github:bartoszj/acextract;
url = "github:bartoszj/acextract";
flake = false;
};
command-line = {
url = github:iHTCboy/CommandLine;
url = "github:iHTCboy/CommandLine";
flake = false;
};
dyld-shared-cache = {
url = github:antons/dyld-shared-cache-big-sur;
dsc-extractor = {
url = "github:keith/dyld-shared-cache-extractor";
flake = false;
};
snapshot-header = {
url = "https://opensource.apple.com/tarballs/xnu/xnu-6153.141.1.tar.gz";
url = "https://github.com/apple/darwin-xnu/archive/refs/tags/xnu-6153.141.1.tar.gz";
flake = false;
};
snap-util = {
url = github:ahl/apfs;
url = "github:ahl/apfs";
flake = false;
};
};
outputs = { self, nixpkgs, acextract, command-line, dyld-shared-cache, snapshot-header, snap-util }: {
acextract =
with import nixpkgs { system = "x86_64-darwin"; };
let xcode12 = makeSetupHook {
deps = [ (xcodeenv.composeXcodeWrapper { version = "12.2"; }) ];
} "${xcbuildHook}/nix-support/setup-hook";
in stdenv.mkDerivation {
name = "acextract-${lib.substring 0 8 self.inputs.acextract.lastModifiedDate}";
src = acextract;
nativeBuildInputs = [ xcode12 ];
preBuild = "LD=$CC";
# FIXME: want to have submodule support for Nix flakes, workaround by explicit instantiation
postUnpack = "rmdir source/CommandLine ; ln -s ${command-line} source/CommandLine";
installPhase = ''
mkdir -p $out/bin
cp Products/Release/acextract $out/bin/
'';
dontStrip = true;
};
dyld-shared-cache =
with import nixpkgs { system = "x86_64-darwin"; };
stdenv.mkDerivation {
name = "dyld-shared-cache-util-${lib.substring 0 8 self.inputs.dyld-shared-cache.lastModifiedDate}";
src = dyld-shared-cache;
nativeBuildInputs = [ xcbuildHook ];
xcbuildFlags = [
"-scheme dyld_shared_cache_util"
"-configuration Release"
"GCC_PREPROCESSOR_DEFINITIONS=CC_DIGEST_DEPRECATION_WARNING=\\\"\\\""
];
installPhase = ''
mkdir -p $out/bin
cp Products/Release/{dsc_extractor.bundle,dyld_shared_cache_util} $out/bin/
'';
};
snap-util =
with import nixpkgs { system = "x86_64-darwin"; };
stdenv.mkDerivation {
name = "snap-util-${lib.substring 0 8 self.inputs.snap-util.lastModifiedDate}";
src = snap-util;
nativeBuildInputs = [ (xcodeenv.composeXcodeWrapper { version = "12.2"; }) ];
preBuild = "NIX_CFLAGS_COMPILE='-idirafter ${snapshot-header}/bsd'";
installPhase = ''
mkdir -p $out/bin
cp snapUtil $out/bin/.snapUtil-wrapped
cat > $out/bin/snapUtil <<- EOF
#!/bin/sh
if csrutil status | grep -Fq disabled && sysctl kern.bootargs | grep -Fq amfi_get_out_of_my_way ; then
exec -a snapUtil $out/bin/.snapUtil-wrapped "\$@"
else
echo 'snapUtil requires SIP and AMFI to be disabled:'
echo ' boot recovery system'
echo ' run csrutil disable'
echo ' run nvram boot-args=amfi_get_out_of_my_way=0x1'
exit 1
fi
EOF
chmod a+x $out/bin/snapUtil
'';
postFixup = ''
cat > snapUtil.entitlements <<- EOF
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>com.apple.developer.vfs.snapshot</key>
<true/>
</dict>
</plist>
EOF
codesign -s - --entitlement snapUtil.entitlements $out/bin/.snapUtil-wrapped
'';
};
outputs = { self, nixpkgs, acextract, command-line, dsc-extractor, snapshot-header, snap-util }: {
packages.x86_64-darwin = {
acextract =
with import nixpkgs { system = "x86_64-darwin"; };
let xcode = makeSetupHook {
deps = [ (xcodeenv.composeXcodeWrapper { version = "14.2"; }) ];
} "${xcbuildHook}/nix-support/setup-hook";
in stdenv.mkDerivation {
name = "acextract-${lib.substring 0 8 self.inputs.acextract.lastModifiedDate}";
src = acextract;
nativeBuildInputs = [ xcode ];
preBuild = "LD=$CC";
# FIXME: want to have submodule support for Nix flakes, workaround by explicit instantiation
postUnpack = "rmdir source/CommandLine ; ln -s ${command-line} source/CommandLine";
# FIXME: fix for Swift compiler crash
patchPhase = ''
patch -p0 <<- EOF
--- acextract/CoreUI.h
+++ acextract/CoreUI.h
@@ -24,6 +24,7 @@
// SOFTWARE.
@import Foundation;
+@import CoreGraphics;
// Hierarchy:
// - CUICatalog:
--- acextract/Operation.swift 2021-10-20 10:35:39.000000000 +0200
+++ acextract/Operation.swift 2021-10-20 10:35:46.000000000 +0200
@@ -24,6 +24,7 @@
// SOFTWARE.
import Foundation
+import ImageIO
// MARK: - Protocols
protocol Operation {
@@ -152,7 +153,7 @@
throw ExtractOperationError.cannotCreatePDFDocument
}
// Create the pdf context
- let cgPage = CGPDFDocument.page(cgPDFDocument) as! CGPDFPage // swiftlint:disable:this force_cast
+ let cgPage = cgPDFDocument.page(at: 0)!
var cgPageRect = cgPage.getBoxRect(.mediaBox)
let mutableData = NSMutableData()
EOF
'';
installPhase = ''
mkdir -p $out/bin
cp Products/Release/acextract $out/bin/
'';
dontStrip = true;
};
dsc-extractor =
with import nixpkgs { system = "x86_64-darwin"; };
stdenv.mkDerivation {
name = "dsc-extractor-${lib.substring 0 8 self.inputs.dsc-extractor.lastModifiedDate}";
src = dsc-extractor;
nativeBuildInputs = [ cmake ];
};
snap-util =
with import nixpkgs { system = "x86_64-darwin"; };
stdenv.mkDerivation {
name = "snap-util-${lib.substring 0 8 self.inputs.snap-util.lastModifiedDate}";
src = snap-util;
nativeBuildInputs = [ (xcodeenv.composeXcodeWrapper { version = "14.2"; }) ];
preBuild = "NIX_CFLAGS_COMPILE='-idirafter ${snapshot-header}/bsd'";
installPhase = ''
mkdir -p $out/bin
cp snapUtil $out/bin/.snapUtil-wrapped
cat > $out/bin/snapUtil <<- EOF
#!/bin/sh
if csrutil status | grep -Fq disabled && sysctl kern.bootargs | grep -Fq amfi_get_out_of_my_way ; then
exec -a ./snapUtil $out/bin/.snapUtil-wrapped "\$@"
else
echo 'snapUtil requires SIP and AMFI to be disabled:'
echo ' boot recovery system'
echo ' run csrutil disable'
echo ' run nvram boot-args=amfi_get_out_of_my_way=0x1'
exit 1
fi
EOF
chmod a+x $out/bin/snapUtil
'';
postFixup = ''
cat > snapUtil.entitlements <<- EOF
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>com.apple.developer.vfs.snapshot</key>
<true/>
<key>com.apple.private.apfs.revert-to-snapshot</key>
<true/>
</dict>
</plist>
EOF
codesign -s - --entitlement snapUtil.entitlements $out/bin/.snapUtil-wrapped
'';
};
};
};
}

View File

@@ -12,7 +12,7 @@ class Converter {
generate() {
const dl = document.createElement("dl");
dl.setAttribute("class", "row");
for (const rowText of this.text.split("\n"))
for (const rowText of this.text.split("\n").slice(1))
if (rowText.length && rowText.toLowerCase().includes(this.filter.toLowerCase()))
dl.append.apply(dl, this.generateRow(rowText));
return dl;
@@ -54,7 +54,7 @@ class Converter {
document.addEventListener("DOMContentLoaded", event => {
// load main content
fetch("internals.txt").then(function(response) {
fetch("internals.tsv").then(function(response) {
if (!response.ok) return "";
return response.text();
}).then(function(text) {
@@ -69,9 +69,11 @@ document.addEventListener("DOMContentLoaded", event => {
document.getElementById("filter").addEventListener("input", event => {
update(event.target.value.length >= 3 ? event.target.value : "");
});
// select filter text on return
// select filter text and update URL on return
document.getElementById("filter").addEventListener("change", event => {
event.target.select();
if (history.pushState)
history.pushState(null, null, "#" + event.target.value);
});
// clear filter button
document.getElementById("clear").addEventListener("click", event => {
@@ -80,7 +82,12 @@ document.addEventListener("DOMContentLoaded", event => {
update("");
});
// initialize filter control
document.getElementById("clear").click();
if (location.hash.length) {
document.getElementById("filter").value = location.hash.slice(1);
document.getElementById("filter").dispatchEvent(new Event("input"));
} else {
document.getElementById("clear").click();
}
});
});
</script>

View File

@@ -1,158 +1,194 @@
Term Description
1TR One True Recovery; booting into macOS recovery on Apple Silicon by holding the power button to verify physical presence; enables interaction with SEP to change Boot Policy
AA Apple account
AA Apple Archive, see also Apple Encrypted Archive; command line tools: aa, aea, compression_tool
AAC Automatic Assessment Configuration; AutomaticAssessmentConfiguration.framework; puts device in a locked mode for exam-style test applications
AAT Apple Advanced Typography; font format and rendering engine
Accounts launchd service: com.apple.accountsd; /System/Library/Accounts
ACDE Apple Connect Device External? ACDEClient.framework, old two-step verification, derived from a company-internal AppleConnect system? server: appleconnect.apple.com
ACDE Apple Connect Device External? ACDEClient.framework, old two-step verification, derived from a company-internal AppleConnect system?
ACFS Apple Clustered File System; deprecated file system for Xsan; acfs.framework
Acoustic ID Siri feature to recognize songs
Action extension type for quick interaction with foreign content within a host app; extension points: com.apple.services, com.apple.ui-services
Activation cryptographic check-in with iCloud to lock devices reported by the user as lost; verified by iBoot; MobileActivationMacOS.framework; launchd service: com.apple.mobileactivationd; servers: humb.apple.com, albert.apple.com
Activity jobs, coarse-grained work units of applications; tracked by the system across XPC, bears a QoS class for scheduling; low-level mechanism not to be confused with User Activity
AE Apple Events; messaging system to invoke application functionality; CoreServices.framework/AE.framework; launchd services: com.apple.coreservices.appleevents, com.apple.AEServer (AE over network)
Aegir astronomy watch face and lock screen; /System/Library/CoreServices/AegirProxyApp.app
AGC Apple Graphics Control, management of multiple displays and display port connections; launchd service: com.apple.displaypolicyd
AHAP Apple Haptic Audio Pattern; file format for simultaneous audio and haptic data; CoreHaptics.framework
AIR Apple Intermediate Representation; synthetic bytecode architecture target for GPU binary toolchain
ALF Application-Level Firewall, launchd service: com.apple.alf (socketfilterfw)
Alloy substrate for communication between user devices over Bluetooth and devices to iCloud, implemented over IDS; /System/Library/IdentityServices/ServiceDefinitions; launchd service: com.apple.identityservicesd
ALS Ambient Light Sensor, AmbientDisplay.framework
Amber Swift UI; SwiftUI.framework
AMFI Apple Mobile File Integrity, checks code integrity based on code signature, stronger enforcement with hardened runtime, validates entitlement restrictions; launchd service: com.apple.MobileFileIntegrity (amfid, invoked by kernel through host special port 18)
AMFI Apple Mobile File Integrity, checks code integrity based on code signature, stronger enforcement with hardened runtime, validates entitlement restrictions; launchd service: com.apple.MobileFileIntegrity (amfid, invoked by kernel through host special port 18); disabled by setting amfi_get_out_of_my_way=0x1 in boot-args
AMP Apple Media Protocol? former parts of iTunes for iPod and iOS device access in Finder, Home Sharing; AMPDevices.framework, AMPSharing.framework; launchd services: com.apple.AMPDeviceDiscoveryAgent, com.apple.AMPDevicesAgent, com.apple.amp.mediasharingd
AMP Asynchronous Multiprocessing; performance and power-efficiency cores on Apple Silicon
AMS Apple Media Services; formerly the iTunes stores and media services: App Stores, Apple Music, Apple TV, iCloud media library, Apple Podcasts, Podcast sync, Books Store, Books sync; AppleMediaServices.framework; server: phobos.apple.com
AMX Apple Matrix Extension; ARM instruction set extension for matrix operations
ANE Apple Neural Engine, hardware accelerator for neural network operations; ANECompiler.framework, ANEServices.framework; launchd service: com.apple.aned
Anisette two-factor authentication creates security codes on trusted devices using TOTP, probably using Circle keys, checked by HSA; AuthKit.framework; launchd service: com.apple.akd
AOP Always On Processor, part of Apple SoCs, runs RTKit as operating system
AOS Apple Online Services? historical name for iCloud
Apache built-in web server; command line tool: apachectl
APFS Apple File System; copy-on-write file system with support for volume space-sharing, per-file encryption, and snapshots
APNS Apple Push Notification service, server infrastructure for remote push notifications over a single connection, clients subscribe to push topics, can be authenticated by app (remote notifications), device (Find My …), or Apple ID login (DSID); credentials in apsd keychain; launchd service: com.apple.apsd; server: push.apple.com
App Nap quiescence detection for applications and corresponding self-demotion in scheduler parameters, implemented within the application by frameworks, listens for occlusion notifications from WindowServer
App Nap quiescence detection for applications and corresponding self-demotion in scheduler parameters, implemented within application frameworks and RunningBoard, listens for occlusion notifications from WindowServer
App Sandbox Seatbelt-based sandbox for apps; /System/Library/Sandbox/Profiles/application.sb; enabled with com.apple.security.app-sandbox entitlement; launchd service: com.apple.secinitd
APT Adaptive Picture Timing? ProMotion; dynamic screen updates with 120Hz base frequency
AppleCare extended warranty; NewDeviceOutreach.framework; launchd service: com.apple.ndoagent
APT Adaptive Picture Timing? ProMotion; dynamic screen updates with 120Hz base frequency; AppleDisplayTCONControl.framework
ASL Apple System Logger, superseded by Unified Logging; /etc/asl; stored in /var/log/asl; launchd service: com.apple.syslogd; command line tool: syslog
ASR Apple Software Restore; restore entire volumes from sources like disk images (HDI, SIU), also restores based on APFS snapshots and snapshot deltas; command line tool: asr
Assertions power state management allowing applications to prevent sleeping; launchd service: com.apple.powerd; command line tools: caffeinate, pmset
Assessment checking of System Policy; term also used for school exam apps that lock the device
Assessment checking of System Policy; term also used for AAC
Asset Cache discretionary caching server for Mobile Assets, Packages, iOS updates, App Store content, ODR, MMCS data; launchd services: com.apple.AssetCache.builtin, com.apple.AssetCacheLocatorService, com.apple.AssetCacheManagerService, com.apple.AssetCacheTetheratorService; command line tools: AssetCacheLocatorUtil, AssetCacheManagerUtil, AssetCacheTetheratorUtil
Assistant Siri; dictation and semantic understanding, Intent is communicated to and enacted on the client, uses TTS; /System/Library/Assistant, AssistantServices.framework; server: *.siri.apple.com
Assistant Siri; dictation and semantic understanding, Intent is communicated to and enacted on the client, uses TTS for output, Snippets to embed mini UIs into responses; /System/Library/Assistant, /System/Library/Snippets, AssistantServices.framework; server: *.siri.apple.com
ATS App Transport Security, sandbox mechanism only allowing TLS-secured connections
ATSUI Apple Type Services for Unicode Imaging; rendering engine superseded by CoreText.framework, font management; ApplicationServices.framework/ATS.framework; launchd service: com.apple.xtyped (fontd); command line tools: atsutil
ATT App Tracking Transparency; apps declare user tracking on app store
Attestation cryptographic proof of a genuine SEP; used for web authentication and app attestation; DeviceCheck.framework; SEP responds to challenge using hardware-key (GID, PKA), online service verifies; used to pair Touch ID keyboards, used to pair RemoteXPC channel?
Authorization discretionary access control policies for high-level services; similar to PAM; policy stored in /var/db/auth.db
Avatar Memoji; AvatarKit.framework
Avatar Memoji and Animoji (face tracking); AvatarKit.framework
AVB Audio Video Bridging, low-latency audio over Ethernet; launchd service: com.apple.avbdeviced; command line tool: avbdiagnose, avbutil
AWD Apple Wireless Diagnostics, sends system telemetry to Apple; CoreAnalytics.framework, WirelessDiagnostics.framework; launchd services: com.apple.awdd, com.apple.analyticsd
AWDL Apple Wireless Direct Link; secondary WiFi interface that runs in parallel to an active WiFi access point connection, similar to WiFi Direct (p2p interface), uses a randomized MAC, used for peer-to-peer networking: AirDrop, AirPlay; DeviceToDeviceManager.framework
Bezel on-screen overlays for hardware volume buttons, screen brightness, Bluetooth HID, and others; /Library/Application Support/Apple/BezelServices, launchd services: com.apple.loginwindow, com.apple.OSDUIHelper
Bifrost emergency satellite connectivity; /System/Library/LocationBundles/Bifrost.bundle
Biome CloudKit-based datastream and sync engine; BiomeStreams.framework, BiomeSync.framework; launchd services: com.apple.BiomeAgent, com.apple.biomesyncd
Blast Door sandboxed sanitization process for untrusted iMessage input; BlastDoor.framework
BOM Bill of Materials; format to store contents of installer Packages; command line tool: lsbom
Bonjour mDNS; launchd service: com.apple.mDNSResponder.reloaded; command line tool: dns-sd
Boot Cache disk cache pre-heating at boot time with typically loaded applications; /var/db/BootCaches; launchd service: com.apple.warmd
Boot Policy decides by signature check which OSes can be booted; boot-time equivalent for System Policy, configurable by SEP on Apple Silicon Macs, enforced by iBoot; command line tools: bputil, kmutil (to enroll custom kernels)
Boot Policy decides by signature check which OSes can be booted, boot-time equivalent for System Policy; LocalPolicy stores user settings, configurable from 1TR, stored by SEP, enforced by iBoot; command line tools: bputil, kmutil (to enroll custom kernels)
BPR Boot Progress Register; set-only flags to track boot mode (normal, DFU, recovery), part of Keybag class key derivation within SEP, so passcode-protected keys are inaccessible in DFU and recovery
Bridge T2 ARM CPU in Intel Macs to drive Touch Bar and Boot Policy; runs bridgeOS, a derivative of watchOS; boots the platform and the Intel CPU, communication from macOS uses RemoteXPC, which uses HTTP/2 over a USB-Ethernet interface; launchd service: com.apple.multiversed, com.apple.remoted; /System/Library/MultiversePlugins; command line tool: remotectl
Bridge T2 ARM CPU in Intel Macs to drive Touch Bar and Boot Policy; runs bridgeOS, a derivative of watchOS; boots the platform and the Intel CPU, communication from macOS uses RemoteXPC; launchd service: com.apple.multiversed; /System/Library/MultiversePlugins
Brook hand washing encouragement on watch; BrookServices.framework
Bulletin Board application push notification management, aggregates local and remote push notifications; BulletinBoard.framework
Cache Delete cleanup for various caches; /System/Library/CacheDelete; launchd service: com.apple.cache_delete (deleted)
CAML Core Animation Markup Language; XML file format for layers, shapes and animations
Carousel derivative of SpringBoard for Watch home screen, watch face, and notification center
Celestial media streaming used by ReplayKit for game broadcasts; Celestial.framework
Certificates validity checked using OCSP stapling, locally installed CRLs, and transparency logs; /System/Library/Security/Certificates.bundle; /var/db/crls; launchd services: com.apple.trustd, com.apple.trustd.agent, com.apple.ocspd; command line tool: crlrefresh
Circle cryptographic primitive to exchange public keys of all trusted devices of one user, signed by all Circle peers; iCloud identity keypair as an additional Circle peer, triggers countersigning from all trusted devices, private key synced across all trusted devices, new devices can pull this key from Secure Backup to join the Circle; used by CKKS; KeychainCircle.framework; command line tools: tpctl, otctl (Octagon trust is newer?)
CKKS CloudKit Key Sync, end-to-end secure syncing for credentials, seeded by Circle, transferred items stored ephemerally using OTR protocol; currently includes ApplePay, AutoUnlock, CreditCards, DevicePairing, Engram, Health, Home, Manatee, SOS, WiFi and other keys; launchd service: com.apple.secd; command line tool: ckksctl
Classroom launchd service: com.apple.studentd
Cloud Pairing part of Alloy, Bluetooth out-of-band pairing over iCloud for Continuity; launchd service: com.apple.cloudpaird
Certificates validity checked using CRLs, OCSP stapling, and transparency logs; /System/Library/Security/Certificates.bundle; launchd services: com.apple.trustd, com.apple.trustd.agent, com.apple.ocspd; command line tool: crlrefresh
Chamois Stage Manager
CHIP Connected Home over IP; Matter; integrated into HomeKit; CHIPPlugin.framework
Circle cryptographic primitive to exchange public keys of trusted devices of a user, signed by Circle peers; iCloud identity added as additional Circle peer, private key synced across all trusted devices, new devices can pull this key from Secure Backup to join the Circle; per-device Circles stored in CKKS for two-factor accounts (Octagon); KeychainCircle.framework; command line tools: tpctl, otctl (Octagon)
CKKS CloudKit Key Sync, end-to-end secure syncing for credentials, seeded by Circle; currently includes ApplePay, AutoUnlock, CreditCards, DevicePairing, Engram, Health, Home, Manatee, SOS, WiFi and other keys; launchd service: com.apple.secd; command line tool: ckksctl
Clarity customizable accessibility mode for simplified UI; ClarityFoundation.framework
Classroom school teachers can create assignments for student iPads and track progress in Schoolwork app; ClassKit.framework; launchd service: com.apple.studentd
Cloud Pairing part of Alloy, Bluetooth out-of-band pairing over iCloud for Continuity; launchd service: com.apple.BTServer.cloudpairing (cloudpaird)
CMAS Commerial Mobile Alert System, now known as Wireless Emergency Alerts (WEA)
Commpage user-mapped kernel data, like vdso/vsyscall on Linux; mapped at 0x7fffffe00000
Communications Filter recipient blocking for iMessage, FaceTime, Mail; launchd service: com.apple.cmfsyncagent
Companion iPhone that is paired with Watch; communication uses Alloy over Bluetooth
Companion iPhone that is paired with Watch; communication uses Alloy over IPsec over Bluetooth
Continuity umbrella term for Handoff, Sidecar, SMS relay, Universal Clipboard, Watch unlock, WiFi call relay and others; SMS relay works by proxying to iMessage, other services use Alloy
Control Center icons in menu/status bar and Bento Box controls UI, gradually replaces SystemUIServer on macOS; handles incoming AirPlay content; launchd services: com.apple.controlcenter, com.apple.SystemUIServer.agent
CPML CorePrediction Machine Learning; CPMLBestShim.framework
CRD Conference Room Display; Apple TV mode
CSR Code Security/Signing Restrictions/Requirements? also called System Integrity Protection (SIP) or rootless mode; collection of kernel-level security restrictions regarding file system modification, unsigned Kexts, Taskport access, NVRAM access, DTrace; /System/Library/Sandbox/rootless.conf; command line tool: csrutil, rootless-init
CTK Crypto Token Kit; smart card management, also for the secure element on iOS? launchd service: com.apple.ctkd; command line tool: sc_auth
CTRR Configurable Text Read-only Region; ARM CPU register to downgrade actual permissions of memory pages; used for JIT protection and by AMFI to freeze user code after checking
Cryptex Cryptographically sealed Extension of SSV, mount-invisible extension of the root volume, allows lightweight updates as part of Rapid Security Response; /System/Cryptexes (mountpoint), /System/Volumes/Preboot/*/cryptex1/current/*.dmg (disk images)
CSR Configurable Security Restrictions; XNU subsystem that is the basis for SIP
CTK Crypto Token Kit; smart card management, also for the Secure Element on iOS? launchd service: com.apple.ctkd; command line tool: sc_auth
CTS Centralized Task Scheduling; execution of DAS tasks; /System/Library/UserEventPlugins/com.apple.cts.plugin
CVMS Core VM Server/Service? compilation of GPU shaders; launchd service: com.apple.cvmsServ
DAAP Digital Audio Access Protocol; used by Home Sharing (with Rapport token) and by the Remote app to control Apple TV (with pairing token); payload unencrypted; DAAPKit.framework; Bonjour services: _atc._tcp, _home-sharing._tcp, _mediaremotetv._tcp, _touch-able._tcp
Daily Briefing Siri giving an overview of information for the day; SiriDailyBriefingInternal.framework
DART DMA Address Relocation Table; IOMMU implementation in Apple silicon, positioned in front of every DMA-capable co-processor and peripheral, offers sub-page protection; SART: streaming variant for high-throughput devices (like NVMe)
DAS Duet Activity Scheduler; scheduling policy engine behind NSBackgroundActivityScheduler and XPC activities; /System/Library/DuetActivityScheduler; launchd service: com.apple.dasd
Data Detectors text analysis to highlight phone numbers, street addresses, and the like; DataDetectors.framework
DataVaults directories with the UF_DATAVAULT special flag; read access limited under CSR
Data Vault directories with the UF_DATAVAULT special flag; CSR limits access to one application
DAV Distributed Authoring and Versioning; network protocol on top of HTTP for syncing calendars (CalDAV), contacts (CardDAV), and formerly also bookmarks (BookmarkDAV)
DCIM Digital Camera Images; DCIMServices.framework
DCP Display Co-Processor
DEP Device Enrollment Program; devices check in with Apple during Setup Assistant to query for their enrollment status, retrieve MDM server URL to fetch initial configuration profile
Developer Mode enables launching of self-compiled apps in iOS, rough equivalent to System Policy; command line tool: devmodectl
DFR Dynamic Function Row?, TouchBar; /System/Library/CoreServices/ControlStrip.app; DFRFoundation.framework
DFU Device Firmware Update; special boot mode where iOS has not booted and the system can be installed over the Lightning connection
Differential Privacy crowdsourcing without user tracking; privacy budget for management of anonymity set; used for keyboard words, emoji, Spotlight searches, Parsec deep links, HealthKit usage, Safari telemetry; /System/Library/DifferentialPrivacy; stored in /var/db/DifferentialPrivacy; launchd service: com.apple.dprivacyd
Digital Separation safety check feature to inhibit sharing relationships; DigitalSeparation.framework
DND Do Not Disturb
DSID Destination Signaling Identifier, unique ID for IDS login on a specific device
DTrace system-wide tracing infrastructure, command line tools: dtrace, *.d, dappprof, dapptrace, dtruss, errinfo, execsnoop, fddist, fs_usage, imptrace, iopattern, iopending, iosnoop, iotop, lastwords, latency, opensnoop, plockstat, rwsnoop, sampleproc, sc_usage, topsyscall, topsysproc
Duet telemetry collection engine for system and user events, forecasting by machine learning, backend for DAS, Proactive, Relevance, Screen Time, thermal and battery management; /System/Library/DuetKnowledgeBase; CoreDuet.framework, CoreKnowledge.framework, CorePrediction.framework; launchd services: com.apple.coreduetd, com.apple.knowledge-agent
Dyld Shared Cache dynamic linker cache, stores all system libraries in prelinked form, original library files are removed; /System/Library/dyld; command line tool: update_dyld_shared_cache
Dyld Shared Cache dynamic linker cache, stores all system libraries in prelinked form, original library files are removed; /System/Volumes/Preboot/Cryptexes/OS/System/Library/dyld; command line tools: dyld_info, dyld_usage, update_dyld_shared_cache
EAS Exchange Active Sync; network protocol for accessing Microsoft Exchange servers
EDR Extended Dynamic Range; rendering with transfer function extending beyond sRGB white; implemented natively on XDR displays and by backlight modulation on others; HDRProcessing.framework
Energy Impact unitless metric for per-application energy consumption, machine-specific coefficients; /usr/share/pmenergy, /usr/share/kpep; launchd services: com.apple.sysmond, com.apple.thermald; command line tool: powermetrics
Engram Messages in iCloud; devices store received iMessages in CloudKit; Engram.framework
Entitlements capability-like attributes bound to executables by code signing; some entitlements like App Sandbox restrict ambient authority, some gradually relieve those restrictions (using Seatbelt), some services or system calls grant privilege based on caller entitlements
ESS IDS user directory, public key distribution for iMessage and CloudKit sharing, uses Transparency; server: *.ess.apple.com; launchd service: com.apple.identityservicesd
Event Monitor simple rules engine for running commands on various systen events; apparently not used by default; /etc/emond.d, /var/db/emondClients; launchd service: com.apple.emond
FaceTime video calls, employs the ICE (establishing peer-to-peer connection), STUN (session credential exchange) and SRTP (encrypted media streaming) protocols; FTServices.framework; launchd services: com.apple.videoconference.camera (avconferenced)
FairPlay DRM system used by app and media stores; CoreADI.framework, CoreFP.framework, CoreLSKD.framework; launchd services: com.apple.adid, com.apple.fairplayd (invoked by kernel through host special port 17), com.apple.lskdd; credentials stored in /var/db/fpsd
Family Circle Family Sharing; launchd services: com.apple.familycircled, com.apple.askpermissiond
FDE Full Disk Encryption, FileVault; command line tool: fdesetup, sysadminctl
FDR Factory Data/Device Reset? ensures that no downgrades are performed? servers: skl.apple.com, gg.apple.com; /System/Library/FDR
Feldspar Apple News; Silex.framework
FiDES Fi? Distributed Evaluation Service? ingests and aggregates Differential Privacy data for unlinkability? used for emoji, Suggestions, Dictation; /System/Library/DistributedEvaluation; DistributedEvaluation.framework; server: fides-pol.apple.com
Find My … location sharing by explicitly querying devices remotely or collateral beacon detection using Search Party; launchd service: com.apple.icloud.fmfd (find my friends)
FiDES Fi? Distributed Evaluation Service? aggregates Differential Privacy data for unlinkability? maybe private federated learning? used for emoji, Suggestions, Dictation; /System/Library/DistributedEvaluation; DistributedEvaluation.framework; server: fides-pol.apple.com
File Provider infrastructure and extension system for syncing with cloud providers; placeholder files based on SF_DATALESS attribute in APFS; FileProvider.framework; locally stored in ~/Library/CloudStorage; command line tool: fileproviderctl
Find My … location sharing by explicitly querying devices remotely or collateral beacon detection using Search Party; FMCore.framework, FMF.framework; launchd service: com.apple.icloud.fmfd (find my friends)
Firmlink bi-directional non-symbolic link between the read-only system volume and the data volume, additional symlinks and mountpoints in the root directory are virtually allocated; /usr/share/firmlinks, /etc/synthetic.conf
Focus restriction modes for notification presentation; focus filters for in-app display restrictions, communicat by Intents; Focus.framework, DoNotDisturb.framework; local settings in ~/Library/DoNotDisturb
FollowUp user interaction for Secure Backup wrapping with device passcode, CoreFollowUp.framework; launchd service: com.apple.followupd
FoundationDB fundamental iCloud storage database, marketed as CloudKit, separated into containers; records, blobs, and large asset storage with MMCS, server-side continuous queries can trigger push notifications, user management by IDS, sharing between users; PCS keys used for hierarchical zone, record, and asset encryption; CloudKitDaemon.framework; launchd service: com.apple.cloudd; locally stored in ~/Library/Caches/CloudKit, ~/Library/Containers/*/Data/CloudKit
FUD Firmware Update Daemon; /var/db/fud; launchd service: com.apple.MobileAccessoryUpdater
FoundationDB fundamental iCloud storage database, marketed as CloudKit, separated into containers; records, blobs, and large asset storage with MMCS, server-side continuous queries can trigger push notifications, user management by IDS, sharing between users; PCS keys used for hierarchical zone, record, and asset encryption; CloudKitDaemon.framework; launchd service: com.apple.cloudd; locally stored in ~/Library/Caches/CloudKit, ~/Library/Containers/*/Data/CloudKit; command line tool: cktool
FPR Fast Permission Restrictions; Apple CPU registers to downgrade (old APRRs do bitmasking) or remap (SPRRs since M1) actual permissions of memory pages (the CTRR region) per thread; used for JIT protection and by AMFI to freeze user code after checking
FUD Firmware Update Daemon; /var/db/fud; launchd service: com.apple.accessoryupdaterd
GID group ID key, shared across all devices of the same SoC generation, derived keys are used to prove device type over the network, only accessible by SEP
Gizmo Apple Watch; watch settings managed by Companion; /Applications/Bridge.app, /System/Library/BridgeManifests
Group Activities SharePlay; sharing of media content and programmatic state over FaceTime calls; GroupActivities.framework, CopresenceCore.framework; launchd service: com.apple.telephonyutilities.callservicesd
GSS Generic Security Service; part of Kerberos; GSS.framework; launchd service: com.apple.gssd (invoked by kernel through host special port 19); command line tool: gsstool
GXF Guarded Execution Feature/Fault, additional exception levels on Apple Silicon, lateral to the usual exception levels; page tables remain the same, but interpretation of permission bits changes by way of FPR, genter and gexit instructions; implements lightweight intra-address-space protection contexts
HAP Home Automation Protocol; CoreHAP.framework
HDA High Definition Audio; HDAInterface.framework
HDI Hard Disk Image; command line tool: hdiutil
HDR High Dynamic Range; video with wide-range transfer function; HDRProcessing.framework
HeadBoard derivative of SpringBoard for tvOS home screen; /Applications/HeadBoard.app, /Applications/PineBoard.app
HLS HTTP Live Streaming
HSA Hardware Security Architecture; version 1 used for two-step verification, SOS with iCSC; version 2 for two-factor authentication, CKKS and Secure Backup with iCDP
HSM Hardware Security Module; HSM fleet runs escrow service for Secure Backup; public keys for authenticating the HSM services in /System/Library/Security/Certificates.bundle/Contents/Resources/AppleESCertificates.plist
HSM Hardware Security Module; HSM fleet runs escrow service for Secure Backup
Hyperion iCloud Photos, uses CloudKit; launchd service: com.apple.cloudphotod; command line tool: cpldiagnose
IAP iPod Accessory Protocol; IAP.framework
iBoot second boot loader stage after UEFI (macOS) or boot ROM (iOS); DFU mode is implemented here; /System/Library/CoreServices/boot.efi
iBoot boot loader stage after boot ROM or UEFI (macOS on Intel); intermediate Low-Level Bootloader (LLB); DFU mode is implemented here; /System/Library/CoreServices/boot.efi
iCDP iCloud Data Protection, codename for a set of enhancements to iCloud privacy: device passcodes used as iCSC for Secure Backup, root keys for CKKS-enabled services only synced between devices and not stored at Apple; launchd service: com.apple.cdpd
iCloud umbrella term for a conglomerate of services, consists of FoundationDB containers with PCS views for key management, supported by CKKS; uses IDS and APNS; some services under the iCloud name are actually served by the iTunes conglomerate or by IMAP or DAV
iCloud umbrella term for a conglomerate of services, consists of FoundationDB containers with PCS views for key management, supported by CKKS; uses IDS and APNS; some services under the iCloud name are actually served by AMS, IMAP, or DAV
iCSC iCloud Security Code, credential wrapping for Secure Backup, previously used a separate code, with HSA2/iCDP uses device passcodes
IDAM Inter-Device Audio and MIDI; audio connection between devices
IDS Identity Service, also IDMS, Apple ID identity management for all of Apples online services; APNS topics for signaling and messaging, see also Alloy, ESS, FaceTime, iMessage; authentication to services with Kerberos
IM Instant Messaging; usually means iMessage and FaceTime, formerly also XMPP
Intent use-case-driven interaction with 3rd-party apps from a host app; used for Siri, Maps, Widgets (configuration); extension points: com.apple.intents-service, com.apple.intents-ui-service
IDV Identity Verification? Touch ID and Face ID; /System/Library/AccessibilityBundles/CoreIDVUI.axbundle
IM Instant Messaging; usually means iMessage and FaceTime
IMG4 boot files (Mach-O binaries or configuration data) with ASN.1 signature, contains RemotePolicy certificate constraints to restrict Boot Policy evaluation
Intent use-case-driven interaction with 3rd-party apps from a host app; used for Siri, Maps, Shortcuts, Widgets (configuration); definition file or programmatically using AppIntents.framework; command line tool: appintentsmetadataprocessor (Xcode extracts Intent definition at compile time); extension points: com.apple.intents-service, com.apple.intents-ui-service
IOKit device driver subsystem for in-kernel and DriverKit drivers, command line tool: ioreg
Ironwood dictation, customized on server with selected user data (contacts, app names, music titles, HomeKit names, Siri Shortcut phrases), not tied to Apple ID; server: guzzoni.apple.com
Ironwood dictation, customized on server with selected user data (contacts, app names, music titles, HomeKit names, Siri Shortcut phrases), not tied to Apple ID; SpeechRecognitionCore.framework; server: guzzoni.apple.com
ISP Image Signal Processor; camera imaging circuit in iPhones
ITML iTunes Markup Language; metdata tagging for media services; ITMLKit.framework
ITP Intelligent Tracking Prevention, cross-site tracking defenses in Safari, statistics and user interaction classify sites, cookies are partitioned and access is restricted
iTunes old umbrella term for a conglomerate of media services: App Stores, Apple Music, Apple TV, iCloud media library, Apple Podcasts, Podcast sync, Books Store, Books sync; server: phobos.apple.com
JARVIS Just A Rather Very Intelligent Scheduler, Mesos cluster manager for Siri, iCloud, iTunes
Jellyfish Animoji
Jetsam reclaiming of purgeable memory and terminatable apps during memory pressure; see TAL
JARVIS Just A Rather Very Intelligent Scheduler, Mesos cluster manager for Siri, iCloud, AMS
Jellyfish Animoji; /Applications/Jellyfish.app
Jetsam reclaiming of purgeable memory and termination of apps during memory pressure
JSC JavaScript Core; JavaScriptCore.framework; command line tool: jsc
Kalamata codename for the transition from x86 to ARM-based Apple Silicon
Kerberos single-sign-on mechanism; Heimdal.framework; command line tools: kinit, ktutil
Kext kernel extension mechanism, loaded at boot time as part of a Kext Collection; /Library/Extensions, /Library/StagedExtensions (for user approval), /System/Library/Extensions; command line tool: kextutil (manages deprecated runtime loading)
Kext Collection prelinked sets of kernel extensions; /System/Library/KernelCollections (for boot and system kexts), /Library/KernelCollections (for auxiliary third-party kexts); the latter is only loaded at a lower-security Boot Policy; launchd service: com.apple.kernelmanagerd (invoked by kernel through host special port 15); command line tool: kmutil
Keybag storage of protection class keys for Keychain and filesystem, protected by SEP with passcode and lockout; stored in user.kb; launchd services: com.apple.mobile.keybagd, com.apple.securityd_service, com.apple.secd
Keybag storage of protection class keys for Keychain and filesystem, protected by SEP using SKP; stored in user.kb; launchd services: com.apple.mobile.keybagd, com.apple.securityd_service, com.apple.secd
Keychain storage for credentials; launchd service: com.apple.securityd; command line tools: certtool, security, systemkeychain
KIP Kernel Integrity Protection, locking of physical memory pages to prevent changes to kernel
Launch Services management for applications, uses Spotlight to update cached info; launchd services: com.apple.coreservices.launchservicesd, com.apple.lsd; CoreServices.framework/LaunchServices.framework; command line tools: lsappinfo, lsregister
Launch Services management for application launches, association of UTIs to apps, uses Spotlight to update cached info; launchd services: com.apple.coreservices.launchservicesd, com.apple.lsd; CoreServices.framework/LaunchServices.framework; command line tools: lsappinfo, lsregister
Live Files user mode filesystems, currently FAT, ExFAT, NTFS on external storage; UserFS.framework, UVFSXPCService.framework; launchd service: com.apple.filesystems.userfsd
Liverpool PCS codename for CloudKit
LKDC Local Key Distribution Center, Kerberos on client machines
LSM Latent Semantic Mapping, text analysis, used for spam filtering, command line tool: lsm
Mac Buddy historic name for Setup Assistant
MAC Policy Mandatory Access Control subsystem in XNU, based on TrustedBSD, implements policy hooks for restricted kernel operations; current policies: AMFI, Seatbelt, Quarantine, CSR
Machine Learning Vision.framework, Espresso.framework, Futhark.framework, PhotoAnalysis.framework
Machine Learning Vision.framework, Espresso.framework, Futhark.framework, PhotoAnalysis.framework; used for Live Text and Visual Lookup; launchd service: com.apple.mediaanalysisd
Madrid iMessage; /System/Library/Messages
Manatee PCS key for some CloudKit containers are synced via CKKS, so data is unreadable to Apple (credential management codenames: Plesio, Stingray, Cuttlefish)
Mandrake emergency siren on Apple Watch Ultra; /Applications/Mandrake.app
Mangrove transfering UI tiles over XPC; Mangrove.framework, IOSurface.framework
Marco Marco.framework, something about IDS and communication (iMessage, Calls), logging?
Marklar codename from the PowerPC era for the port to x86, served the transition to Intel CPUs
Marzipan Catalyst; port of iOS frameworks to macOS, Catalyst apps are iOS apps with additional API to adapt macOS UI idioms; /System/iOSSupport; integration using UIKit system process; launchd service: com.apple.uikitsystemapp
Marzipan Catalyst; port of iOS frameworks to macOS, Catalyst apps are iOS apps with additional API to adapt macOS UI idioms; /System/iOSSupport; integration using UIKit system process; launchd service: com.apple.uikitsystemapp; input remapping by /Library/Apple/Library/Bundles/InputAlternatives.bundle
MCX Managed Client for OS X, preference management for settings from configuration profiles, /Library/Managed Preferences, command line tools: mcxquery, mcxrefresh
MDM Mobile Device Management; server software to manage fleets of iOS and macOS devices; uses configuration profiles to manage preferences; ConfigurationProfiles.framework
MDS Module Directory Services, ancient part of the old security APIs (CSDA, CSSM)
Memory Debugging uses Taskport; command line tools: heap, leaks, malloc_history, stringdups, vmmap
Mesa Touch ID; /Library/Catacomb; /var/db/bkad.db
Metadata Spotlight; file indexing on macOS; CoreServices.framework/Metadata.framework, CoreServices.framework/SearchKit.framework; stored in .Spotlight-V100; launchd service: com.apple.metadata.mds; command line tools: mddiagnose, mdfind, mdimport, mdls, mdutil; in addition to auto-indexing, apps can explicitly register searchable items; CoreSpotlight.framework; launchd service: com.apple.corespotlightd
MMCS MobileMe Chunk Storage, used by iCloud, splits blobs into chunks and stores them at Amazon/Google with convergent encryption; MMCS.framework
MMCS MobileMe Chunk Storage, used by iCloud, splits blobs into chunks and stores them at Apple/AWS/GCP with convergent encryption (content hash as key); MMCS.framework
Mobile prefix for iOS
Mobile Assets demand-downloaded system components like fonts, dictionaries, linguistic data; stored in /System/Library/Assets; launchd services: com.apple.languageassetd (language-dependent assets), com.apple.mobileassetd; server: mesu.apple.com
Mobile Device connectivity to iOS devices over USB or WiFi (AirTrafficHost) for syning, development, and debugging; MobileDevice.framework; launchd service: com.apple.usbmuxd; Bonjour service: _apple-mobdev2._tcp
@@ -161,14 +197,14 @@ Mondrian photo collage arrangement in Photos.app; Mondrian.framework
MRT Malware Removal Tool; /Library/Apple/System/Library/CoreServices/MRT.app
Multipeer Connectivity ad-hoc networking; Bonjour for discovery; WiFi, AWDL, Bluetooth, or Ethernet as transport; optional encryption and certificate-based authentication; MultipeerConnectivity.framework
Nano prefix for watchOS
Neural Engine hardware accelerator for neural network operations; ANECompiler.framework, ANEServices.framework; launchd service: com.apple.aned
Nearby Interaction proximity-based interaction between devices; proximity measured using ultra wideband or derived from other technologies; used for Universal Control; NearbyInteraction.framework, Proximity.framework; launchd service: com.apple.nearbyd
Newton fall detection on watchOS
NLP Natural Language Processing; NLP.framework; related to mecabra libraries, a linguistic engine for Chinese and Japanese; /usr/share/mecabra, /usr/share/tokenizer
Notarization app security scan by Apple; cryptographic proof stapled to code signature, tested at launch by System Policy; for non-notarized apps sends code hash to Apple; command line tools: altool, stapler
Notarization app security scan by Apple; cryptographic proof stapled to code signature, tested at launch by System Policy; for non-notarized apps sends code hash to Apple; command line tools: notarytool, altool, stapler
Noticeboard User Notifications for Software Update and App Store, Noticeboard.framework; launchd services: com.apple.noticeboard.state (nbstated), com.apple.noticeboard.agent (nbagent)
Notifications system notification bus, unrelated to the local/remote push notifications; launchd service: com.apple.notifyd, com.apple.kuncd (invoked by kernel through host special port 10); command line tool: notifyutil; complemented by framework-level notification system (CFNotification, NSNotification); launchd services: com.apple.distnoted.xpc.daemon, com.apple.distnoted.xpc.agent
NSP Network Service Proxy; per-app VPN and proxy settings; launchd service: com.apple.networkserviceproxy
OAH Rosetta
NSP Network Service Proxy; per-app VPN and proxy settings, implements Private Relay; launchd service: com.apple.networkserviceproxy
OAH Rosetta; ahead-of-time compiler for Intel code on Apple Silicon; /usr/libexec/rosetta
ODR On-Demand Resources; loaded from App Store; launchd service: com.apple.appstored
Onboarding data protection splash screen shown by service-connected apps; /System/Library/OnBoardingBundles; OnBoardingKit.framework
Open Directory directory service for user, group, and machine management; plugin-based to use different backend stores (LDAP, Active Directory), local accounts in /private/var/db/dslocal; launchd service: com.apple.opendirectoryd; command line tools: dscacheutil, dscl, dsconfigad, dsconfigldap, dseditgroup, dsenableroot, dserr, dsexport, dsimport, dsmemberutil, odutil
@@ -177,85 +213,109 @@ OSA Open Scripting Architecture; scripting of applications from different fonten
OTUT One-Time Unlock Token; security mechanism to allow keybag unwrapping after updates
PAC Pointer Authentication Codes; pointers signed in unused bits to prevent ROP attacks
Packages unit of software installation; command line tools: pkgutil, installer, softwareupdate; launchd services: com.apple.softwareupdated, com.apple.bootinstalld, com.apple.installd, com.apple.system_installd, com.apple.uninstalld; /var/db/softwareupdate, /Library/Apple/System/Library/Receipts (system), /System/Library/Receipts (read-only), /private/var/db/receipts (App Store)
Packet Filter network traffic filtering subsystem from OpenBSD; command line tool: pfctl
Parsec Spotlight web results and searching of crowdsourced User Activity deep links; server: *.smoot.apple.com; launchd services: com.apple.parsecd, com.apple.parsec-fbf (Feedback Flush to Differential Privacy)
Pasteboard storage for cut, copy, and paste; launchd service: com.apple.pboard; command line tools: pbcopy, pbpaste
Password Breach monitoring of Keychain passwords against a breach database; round-robin matching in fixed-size batches, local match against common leaks, remote match using hash prefix; launchd service: com.apple.Safari.passwordbreachd
Pasteboard storage for cut, copy, and paste; type of content remembered as UTI; launchd service: com.apple.pboard; command line tools: pbcopy, pbpaste
PCS Protected Cloud Storage; key management for separate iCloud storage compartments (PCS calls them views), each can contain FoundationDB plus bulk data stored by MMCS; see also iCDP, CKKS, Manatee; ProtectedCloudStorage.framework; /System/Library/Preferences/ProtectedCloudStorage; command line tool: pcsstatus
PCSC Personal Computer Smart Card; PCSC.framework, uses CTK
PDE Print Dialog Extension; old name, not a proper Extension
Pegasus picture-in-picture video playback; Pegasus.framework (iOS), PIP.framework (macOS)
Pegasus meaning 1: picture-in-picture video playback; Pegasus.framework (iOS), PIP.framework (macOS); meaning 2: online search query engine for visual lookup; PegasusKit.framework
Pepper UI elements for Watch home screen and Chat, like Quickboard (canned replies), Animoji; PepperUICore.framework
Persona separation of sub-user-identities, like when using a private and managed Apple account; PersonaKit.framework; ~/Library/Personas; /System/Library/UserManagement
Persona separation of sub-user-identities, like when using a private and managed Apple account; PersonaKit.framework; ~/Library/Personas; /System/Library/UserManagement; command line tool: umtool
PHASE Physical Audio Spatialization Engine; 3D sound rendering engine; Apple devices map audio sources (even mono and stereo) to virtual speakers in a 3D sound stage, which is simulated by the physical speakers via a head-related transfer function; PHASE.framework
Piano Mover Mail Drop; bulk mail attachments transfered over PCS; not to be confused with storage for iMessage attachments, which uses a CloudKit container
Plugin Extensions, XPC services bundled with apps or frameworks, discovery by Launch Services; launchd service: com.apple.pluginkit.pkd; command line tool: pluginkit
PMP Port Mapping Protocol; Apple alternative to UPnP, Bonjour service: _acp-sync._tcp
Poster iPhone lock screen; PosterBoard.framework, PosterKit.framework
PowerUI battery management like smart charge and power save, learns from Duet and other data; PowerUI.framework; /var/db/PowerUI; launchd service: com.apple.PowerUIAgent
Preferences storage for user-configurable settings; launchd services: com.apple.cfprefsd.xpc.daemon, com.apple.cfprefsd.xpc.agent; stored in Library/Preferences, command line tool: defaults; interaction with Synced Defaults per /System/Library/DefaultsConfigurations
Private Relay two-hop onion routing with one entry and one exit node; Apple operates entry, third-party services operate exit nodes; QUIC for payload, ODoH for DNS, approximate IP geolocation via Waldo; authentication via Attestation, propagated to proxys using RSA blind signatures
Proactive umbrella term for suggestions and completions based on Duet forecasting and User Activity context, also marketed as Siri features; PersonalizationPortrait.framework
QoS Classes inheritable property for Activities; semantic priorities, influences scheduling parameters; initially set at user-level, priority inheritance within GCD queues and across XPC in kernel?
Quagga framework for QR and barcode decoding; Quagga.framework
Quick Action extension type for quick interaction with foreign content within a host app; extension points: com.apple.services, com.apple.ui-services
Quick Look file preview and thumbnail generation; comand line tool: qlmanage
RAOP Remote Audio Output Protocol, AirPlay; Bonjour service: _raop._tcp
Rapport device pairing by proximity using Alloy, with PIN entry, or using iCloud; once paired, devices can access services; used for HomeKit, HomePod, AirPlay, Home Sharing, SideCar; Rapport.framework; launchd service: com.apple.rapportd; Bonjour service: _companion-link._tcp
Recents recently used items (not files) in various applications, synced with Synced Defaults; CoreRecents.framework, /System/Library/Recents; launchd service: com.apple.recentsd
Relevance Engine backend for Siri suggestions (for example of Siri Shortcuts), Siri watch face, Widget smart stacks; consumes Duet knowledge and app-provided timelines; /System/Library/RelevanceEngine; launchd service: com.apple.relevanced
Relevance Engine backend for Siri suggestions (for example of Siri Shortcuts), Widget smart stacks (also Siri watch face); consumes Duet knowledge and app-provided timelines with relevance hints; /System/Library/RelevanceEngine; launchd service: com.apple.relevanced
Remote Pairing Mobile Device pairing without wired connection; RemotePairingDevice.framework; Bonjour services: _remotepairing._tcp, _remotepairing-manual-pairing._tcp
RemoteXPC connection to a non-SoC-integrated SEP like Bridge; uses HTTP/2 over a network interface, Bridge connected over USB, secured using Attestation; RemoteServiceDiscovery.framework, TrustedAccessory.framework; launchd service: com.apple.remoted, com.apple.tracd; command line tool: remotectl
Revisions document autosave and auto-versioning; stored in .DocumentRevisions-V100; GenerationalStorage.framework; launchd service: com.apple.revisiond
Routine frequently visited locations on iOS, interacts with Duet; launchd service: com.apple.routined
RTC Real-time Telemetry and Crash reporting; RTCReporting.framework; launchd service: com.apple.rtcreportingd
RTKit operating system used on Apple Silicon for firmware of co-processors
RunningBoard runtime management of apps, paradigm: app as service process invoked by system, check-in by frameworks, handles process assertions (frontmost app, see App Nap), memory pressure (see Jetsam) and compute resources (GPU), replacement for TAL?; launchd service: com.apple.runningboardd; /System/Library/LifecyclePolicy, /System/Library/RunningBoard
SBPL Sandbox Profile Language; a TinyScheme-based embedded DSL for Seatbelt profiles
SCIP System Coprocessor Integrity Protection; like KIP, but for SEP, ISP, Motion coprocessor
Screen Reader VoiceOver and Braille; /System/Library/ScreenReader; ScreenReader.framework
Screen Time digital wellbeing and parental controls system, uses Device Management as policy engine, self-enforced within the application by frameworks; launchd services: com.apple.ScreenTimeAgent, com.apple.dmd
Screen Time digital wellbeing and parental controls system, uses Device Management as policy engine, self-enforced within the application by frameworks; DeviceActivity.framework, ManagedSettings.framework, FamilyControls.framework; launchd services: com.apple.ScreenTimeAgent, com.apple.dmd
SDB SQL Database; CoreSDB.framework, used by iCloud communication
Search Party portion of Find My service for offline devices; devices emit public part of rotating key pair via Bluetooth LE, other devices encrypt current location with this key and send to Apple, private key shared over CloudKit
Seatbelt process sandbox by filtering system calls; /System/Library/Sandbox/Profiles, /usr/share/sandbox; profiles written in a SBPL; command line tool: sandbox-exec; launchd service: com.apple.sandboxd (invoked by kernel through host special port 14 for logging)
Secure Backup escrow part of CKKS; escrow key individually wrapped with passcodes of trusted devices, stored in HSM to prevent brute forcing, uses SRP so passcodes are not visible to iCloud, limited number of recovery attempts; protocol called Lakitu, uses FollowUp; launchd service: com.apple.SecureBackupDaemon; CloudServices.framework
SEP Secure Enclave Processor; dedicated ARM core for security services, runs L4/Darbat, inline encryption to DRAM, factory-paired channels to Touch ID/Face ID hardware and Secure Element; SEP can use but not read device UID key, usage restricted to ROM code
Seatbelt process sandbox by filtering system calls; profiles written in SBPL; /System/Library/Sandbox/Profiles, /usr/share/sandbox; default file access policy asks for TCC confirmation before access to folders with user data (like Documents) is allowed; command line tool: sandbox-exec; launchd service: com.apple.sandboxd (invoked by kernel through host special port 14 for logging)
Secure Backup escrow part of CKKS; escrow key individually wrapped with passcodes of trusted devices, stored in HSM to prevent brute forcing, uses SRP so passcodes are not visible to iCloud, limited number of recovery attempts; protocol called Lakitu, uses FollowUp; launchd service: com.apple.SecureBackupDaemon (com.apple.sbd); CloudServices.framework
SEP Secure Enclave Processor; dedicated ARM core for security services, runs L4/Darbat-based sepOS, inline encryption to DRAM, manages AES keys in storage DMA engine, factory-paired channels to Touch ID/Face ID hardware, Secure Element, Neural Engine; SEP can use but not read UID and GID keys; credential verification performed by hardware lockbox with retry count enforcement
Sequoia translation; downloadable language models can run on-device; /Applications/SequoiaTranslator.app, Translation.framework
Seymour Apple Fitness+; workout videos integrated with Watch sensors; SeymourCore.framework
SF Symbols scalable UI symbols; rendered with various color treatments; SFSymbols.framework
Sharing umbrella term for wireless proximity services: AirDrop, Continuity, Instant Hotspot, WiFi sharing; used by loginwindow for Watch unlock; Sharing.framework; launchd service: com.apple.sharingd; also serves connection sharing and remote disk
Shazam audio (especially music) recognition service; ShazamKit.framework; launchd service: com.apple.shazamd; command line tool: shazam
Shoebox Passbook
Sidecar using iPhone/iPad as Mac accessory: camera for photos and scanning, annotations, external display over low-latency WiFi (llw interface) using avconferenced encoding; SidecarCore.framework; launchd services: com.apple.sidecar-display-agent (SidecarDisplayAgent), com.apple.sidecar-relay (SidecarRelay)
Sidecar using iPhone/iPad as Mac accessory: external camera and microphone (ContinuityCapture), camera for photos and scanning (DocumentCamera.framework), external display over low-latency WiFi (llw interface) using avconferenced encoding; SidecarCore.framework; launchd services: com.apple.sidecar-display-agent (SidecarDisplayAgent), com.apple.sidecar-relay (SidecarRelay)
Signpost telemetry API to report points of interest in code; launchd service: com.apple.signpost.signpost_reporter
Simulator running an iOS/tvOS/watchOS personality on macOS, uses sandboxing and a separate Mach bootstrap namespace for container-like isolation, command line tool: simctl
Simulator running an iOS/tvOS/watchOS personality on macOS, uses sandboxing and a separate Mach bootstrap namespace for container-like isolation; installable simulators as disk images in /Library/Developer/CoreSimulator/Images; command line tool: simctl
SIP System Integrity Protection or rootless mode; collection of kernel-level security restrictions regarding file system modification, unsigned Kexts, Taskport access, NVRAM access, DTrace; /System/Library/Sandbox/rootless.conf; command line tool: csrutil, rootless-init
Site Association signed files in .well-known directory on websites; equivalent to Entitlements for websites, associates domains with app IDs for Universal Links; command line tool: swcutil
SKP Sealed Key Protection; measurement of system state (boot chain IMG4 manifests, BPR, Boot Policy data, UID key, user passcode) to derive Keybag keys
SKS Secure Key Store; handling of keybag keys within the SEP
SkyLight WindowServer; SkyLight.framework
Skywalk network subsystem in XNU, links together actual technologies (Bluetooth, WiFi, Thunderbolt) and interfaces/tunnels; transacts in nexus (for conduits) and agent (for endpoints) objects; command line tool: skywalkctl
Skywalk network subsystem in XNU, links together actual technologies (Bluetooth, WiFi, Thunderbolt) and interfaces/tunnels; transacts in nexus (for conduits) and agent (for endpoints) objects; DriverKit network drivers use Skywalk; command line tool: skywalkctl
SLC System-Level Cache, architectural feature of Apple Silicon; cache located within SoC at controllers for external DRAM, serves all compute units and stages transfers between them
Social Gaming Game Center; multiplayer gaming services on top of CloudKit, shared storage and low-latency multicast for multiplayer sessions; launchd service: com.apple.gamed
Sock Puppet Watch interaction that requires Companion device
SOS Secure Object Sync; syncing backend for iCloud Keychain, not to be confused with the emergency call feature; transferred items previously staged in Synced Defaults, now uses CKKS; launchd services: com.apple.secd (access to local keychain), com.apple.security.cloudkeychainproxy3 (connects to Synced Defaults), com.apple.security.keychain-circle-notification
SOS Secure Object Sync; syncing backend for iCloud Keychain, not to be confused with the emergency call feature; transferred items previously staged in Synced Defaults, for two-factor accounts in CKKS; launchd services: com.apple.secd (access to local keychain), com.apple.security.cloudkeychainproxy3 (connects to Synced Defaults), com.apple.security.keychain-circle-notification
SPI System Private Interface; /System/Library/PrivateFrameworks
SpringBoard iOS home screen; like Dock (Launchpad, Mission Control, desktop picture), Control Center, SystemUIServer (menu extras icons), loginwindow (lock screen), and WindowServer (compositor) on macOS; /System/Library/CoreServices/SpringBoard.app, /Applications/PreBoard.app, BaseBoard.framework, FrontBoard.framework, SplashBoard.framework, /System/Library/RunningBoard; launchd service: com.apple.backboardd (compositor)
SpringBoard iOS home screen; like Dock (Launchpad, Mission Control, desktop picture), Control Center, SystemUIServer (menu extras icons), loginwindow (lock screen), and WindowServer (compositor) on macOS; /System/Library/CoreServices/SpringBoard.app, /Applications/PreBoard.app, BaseBoard.framework, FrontBoard.framework, SplashBoard.framework; launchd service: com.apple.backboardd (compositor)
SPRR Shadow Permission Remap Register? feature of Apple Silicon to dynamically reintepret page permissions
SRP Secure Remote Password; standard cryptographic protocol for proving knowledge of a secret such that attackers cannot brute-force the secret; AppleSRP.framework
SSO Single Sign-On
SSV Signed System Volume, als called Authenticated Root Volume (ARV); macOS boots from blessed read-only APFS snapshot, merkle-tree and root-hash stored in Preboot volume; modifications require disabling root authentication with csrutil from recovery, then the live filesystem can be mounted, modified, and re-blessed; command line tools: apfs_systemsnapshot, bless, csrutil
Stark CarPlay
Stockholm Apple Pay; also Warsaw
Stockholm Secure Element in Apple SoCs, a processor running crypto protocols on keys it protects; used for Apple Pay and Car Key; related codenames: Icefall, Warsaw
Storage Management freeing up disk space by managing bulky items; UI in System Information.app; StorageManagement.framework; launchd service: com.apple.diskspaced; extension point: com.apple.storagemanagement; extends Cache Delete service
Suggestions semantic analysis of mails and websites to suggest contacts, calendar events and the like; launchd services: com.apple.suggestd, com.apple.reversetemplated; custom JavaScript parsers in /System/Library/AssetsV2/com_apple_MobileAsset_CoreSuggestions
Symbols debug symbols for backtraces; CoreSymbolication.framework; launchd services: com.apple.coresymbolicationd; command line tools: symbols, symbolscache
Symbols debug symbols for backtraces; CoreSymbolication.framework; launchd services: com.apple.coresymbolicationd; command line tools: atos, symbols, symbolscache
Symptoms network diagnostics; Symptoms.framework; /var/networkd/db/netusage.sqlite; launchd service: com.apple.symptomsd (invoked by kernel through host special port 27)
Synced Defaults simple key-value store for applications, no user control over data; can use iCloud key-value backend (old) or Manatee container (new, marked as com.apple.kvs) as storage; launchd service: com.apple.syncdefaultsd; locally stored in ~/Library/SyncedPreferences
System Configuration SystemConfiguration.framework; launchd service: com.apple.configd; command line tool: scutil
System Extension user-level components formerly in the kernel; currently either a DriverKit, Network, or Endpoint Security extension; /System/DriverKit, /System/Library/DriverExtensions; command line tool: systemextensionsctl; launchd services: com.apple.sysextd, com.apple.nesessionmanager, com.apple.endpointsecurity.endpointsecurityd
System Policy Gatekeeper; policy engine for application launches and kext loading; /var/db/SystemPolicy; launchd service: com.apple.security.syspolicy (invoked by kernel through host special port 29); command line tool: spctl
TAL Transparent App Lifecycle; app process is started and stopped independently of the user launching and quitting app; also handles session restore across reboots; ~/Library/Saved Application State; launchd service: com.apple.talagent
System Extension user-level components formerly in the kernel; currently either a DriverKit, Network, or Endpoint Security extension; /System/DriverKit, /System/Library/DriverExtensions; command line tool: systemextensionsctl; launchd services: com.apple.sysextd, com.apple.nesessionmanager, com.apple.endpointsecurity.endpointsecurityd; command line tool: eslogger
System Policy Gatekeeper; policy engine for application launches and kext loading, malware signatures from /Library/Apple/System/Library/CoreServices/XProtect.bundle; /var/db/SystemPolicy; launchd service: com.apple.security.syspolicy (invoked by kernel through host special port 29); command line tool: spctl
TAL Transparent App Lifecycle; process for macOS apps started and stopped independently of the user launching and quitting app; also handles session restore across reboots; ~/Library/Saved Application State; launchd service: com.apple.talagent
Taskport Mach kernel concept for ptrace-like access to task internals; access policy implemented by daemon; launchd service: com.apple.taskgated (invoked by kernel through task special port 9); command line tool: DevToolsSecurity
TCC Transparency, Consent, and Control; user control over app access to privacy-related services (kTCCService*); TCC.framework; launchd services: com.apple.tccd, com.apple.tccd.system; command line tool: tccutil; stored in /Library/Application Support/com.apple.TCC, ~/Library/Application Support/com.apple.TCC, /var/db/locationd (for kTCCServiceLocation)
Time Machine automatic backup service, command line tools: tmdiagnose, tmutil
Tin Can Walkie Talkie on watchOS
Tones ringtones; ToneLibrary.framework
Tourist backend for user-visible tips and hints; launchd service: com.apple.touristd
Translocation app binary copied on launch to dedicated location; initiated by Launch Services for security (prevents path traversal for apps quarantined by System Policy) or path normalization (iOS apps do not expect to be moved, but can be moved on macOS)
Transparency key transparency for ESS keys? Transparency.framework; launchd service: com.apple.transparencyd; server: init-kt.apple.com
TTS Text To Speech, command line tool: say; /System/Library/Speech; synthesizer engines: MacinTalk (historic), Polyglot (phoneme-based?), Gryphon (current, DNN-based?)
TSS Tatsu Signing Server; online verification for firmware signatures; server: gs.apple.com
TTS Text To Speech, neural-network-based synthesis engine (Gryphon); command line tool: say; /System/Library/Speech, /System/Library/TTSPlugins
TVML TV Markup Language; declarative UI language for TV apps; TVMLKit.framework
Ubiquity iCloud Drive; uses CloudKit, codename Bladerunner; CloudDocs.framework; command line tools: fileproviderctl; launchd service: com.apple.bird (iclouddrive-agent); locally stored in ~/Library/Mobile Documents (was supposed to move to Library/CloudStorage/iCloud Drive and iclouddrivectl but this was reverted)
Ubiquity iCloud Drive; codename Bladerunner, uses CloudKit; CloudDocs.framework; launchd service: com.apple.bird; locally stored in ~/Library/Mobile Documents (was supposed to move to Library/CloudStorage/iCloud Drive but this was reverted)
UID unique ID key, used as root key for cryptographic subsystems, generated during manufacturing by SEP and fused into hardware, only accessible by SEP
Unified Logging system-wide logging and Activity tracking; launchd service: com.apple.logd, com.apple.diagnosticd; command line tool: log; /dev/oslog; data stored in /var/db/diagnostics, support files in /var/db/uuidtext
User Activity abstraction behind deep-linking into apps with structured context data (people, places); used for Universal Links (with schema.org on websites), Handoff, Parsec, Siri Shortcuts, Proactive; UserActivity.framework; launchd service: com.apple.coreservices.useractivityd
USD Universal Scene Description; storage format for 3D assets; /usr/lib/usd
User Activity abstraction for deep-linking into apps with structured context (people, places); used for Universal Links (schema.org on websites), Handoff, Parsec (app links in search), Siri Shortcuts, Quick Note (context awareness), Proactive; UserActivity.framework; launchd service: com.apple.coreservices.useractivityd
User Notifications user interface for notification center; launchd service: com.apple.usernoted
UTI Uniform Type Identifiers; system for document types; file extensions and MIME types are mapped to UTIs, UTIs form a conformance graph, apps register their UTIs with Launch Services; /System/Library/CoreServices/CoreTypes.bundle; also Apples hardware devices are represented as UTIs
VA Video Acceleration; AppleGVA.framework, AppleVA.framework, AppleVPA.framework
Viceroy video conferencing used by FaceTime and ReplayKit
Viceroy video conferencing used by FaceTime and ReplayKit; ViceroyTrace.framework
VSDB volume status database; /var/db/volinfo.database; command line tool: vsdbutil
Waldo VPN key management? location aware? seen in NSP, server: waldo.apple.com
Waldo selects edge servers based on approximate location, part of Private Relay, seen in NSP
WFS WebDAV File Sharing; built-in file sharing with Apache; /etc/wfs; command line tool: wfsctl
Widgets content excerpt from apps; provided via a timeline of views, configuration uses Intents; extension point: com.apple.widgetkit-extension
Widgets content excerpt from apps; provided via a timeline of view hierarchies, configuration uses Intents; visible on home screen, lock screen, as live activities, as watch complications; WidgetKit.framework; extension point: com.apple.widgetkit-extension
Willow HomeKit; end-to-end-encrypted communication protocol and API for IoT-accessories; pairing with SRP using code printed on device, credential sync by CKKS, transported over Alloy, remote access using Apple TV as proxy; launchd service: com.apple.homed
xART persistent storage for SEP, used by Mesa; /System/Volumes/xarts; launchd service: com.apple.xartstorageremoted; command line tool: xartutil
Workflow Shortcuts; user-programmable system-wide automation, built-in triggers cause a chain of actions to run; actions are synthesized from User Activities and Intents provided by apps; WorkflowKit.framework, ActionKit.framework; locally stored in ~/Library/Shortcuts; launchd service: com.apple.siriactionsd (voice-triggered shortcuts); command line tool: shortcuts
xART eXtended Anti-Replay Technology; persistent storage for SEP, used by Mesa; /System/Volumes/xarts; launchd service: com.apple.xartstorageremoted; command line tool: xartutil
XCS Xcode Server; continuous integration server; command line tools: xcscontrol, xcsdiagnose
1 AA Term Apple account Description
1 Term Description
2 1TR One True Recovery; booting into macOS recovery on Apple Silicon by holding the power button to verify physical presence; enables interaction with SEP to change Boot Policy
3 AA AA Apple account Apple account
4 AA Apple Archive, see also Apple Encrypted Archive; command line tools: aa, aea, compression_tool
5 AAC Automatic Assessment Configuration; AutomaticAssessmentConfiguration.framework; puts device in a locked mode for exam-style test applications
6 AAT AAT Apple Advanced Typography; font format and rendering engine Apple Advanced Typography; font format and rendering engine
7 Accounts Accounts launchd service: com.apple.accountsd; /System/Library/Accounts launchd service: com.apple.accountsd; /System/Library/Accounts
8 ACDE ACDE Apple Connect Device External? ACDEClient.framework, old two-step verification, derived from a company-internal AppleConnect system? server: appleconnect.apple.com Apple Connect Device External? ACDEClient.framework, old two-step verification, derived from a company-internal AppleConnect system?
9 ACFS ACFS Apple Clustered File System; deprecated file system for Xsan; acfs.framework Apple Clustered File System; deprecated file system for Xsan; acfs.framework
10 Acoustic ID Acoustic ID Siri feature to recognize songs Siri feature to recognize songs
11 Action Activation extension type for quick interaction with foreign content within a host app; extension points: com.apple.services, com.apple.ui-services cryptographic check-in with iCloud to lock devices reported by the user as lost; verified by iBoot; MobileActivationMacOS.framework; launchd service: com.apple.mobileactivationd; servers: humb.apple.com, albert.apple.com
12 Activity Activity jobs, coarse-grained work units of applications; tracked by the system across XPC, bears a QoS class for scheduling; low-level mechanism not to be confused with User Activity jobs, coarse-grained work units of applications; tracked by the system across XPC, bears a QoS class for scheduling; low-level mechanism not to be confused with User Activity
13 AE AE Apple Events; messaging system to invoke application functionality; CoreServices.framework/AE.framework; launchd services: com.apple.coreservices.appleevents, com.apple.AEServer (AE over network) Apple Events; messaging system to invoke application functionality; CoreServices.framework/AE.framework; launchd services: com.apple.coreservices.appleevents, com.apple.AEServer (AE over network)
14 Aegir astronomy watch face and lock screen; /System/Library/CoreServices/AegirProxyApp.app
15 AGC AGC Apple Graphics Control, management of multiple displays and display port connections; launchd service: com.apple.displaypolicyd Apple Graphics Control, management of multiple displays and display port connections; launchd service: com.apple.displaypolicyd
16 AHAP Apple Haptic Audio Pattern; file format for simultaneous audio and haptic data; CoreHaptics.framework
17 AIR Apple Intermediate Representation; synthetic bytecode architecture target for GPU binary toolchain
18 ALF ALF Application-Level Firewall, launchd service: com.apple.alf (socketfilterfw) Application-Level Firewall, launchd service: com.apple.alf (socketfilterfw)
19 Alloy Alloy substrate for communication between user devices over Bluetooth and devices to iCloud, implemented over IDS; /System/Library/IdentityServices/ServiceDefinitions; launchd service: com.apple.identityservicesd substrate for communication between user devices over Bluetooth and devices to iCloud, implemented over IDS; /System/Library/IdentityServices/ServiceDefinitions; launchd service: com.apple.identityservicesd
20 ALS ALS Ambient Light Sensor, AmbientDisplay.framework Ambient Light Sensor, AmbientDisplay.framework
21 Amber Amber Swift UI; SwiftUI.framework Swift UI; SwiftUI.framework
22 AMFI AMFI Apple Mobile File Integrity, checks code integrity based on code signature, stronger enforcement with hardened runtime, validates entitlement restrictions; launchd service: com.apple.MobileFileIntegrity (amfid, invoked by kernel through host special port 18) Apple Mobile File Integrity, checks code integrity based on code signature, stronger enforcement with hardened runtime, validates entitlement restrictions; launchd service: com.apple.MobileFileIntegrity (amfid, invoked by kernel through host special port 18); disabled by setting amfi_get_out_of_my_way=0x1 in boot-args
23 AMP AMP Apple Media Protocol? former parts of iTunes for iPod and iOS device access in Finder, Home Sharing; AMPDevices.framework, AMPSharing.framework; launchd services: com.apple.AMPDeviceDiscoveryAgent, com.apple.AMPDevicesAgent, com.apple.amp.mediasharingd Apple Media Protocol? former parts of iTunes for iPod and iOS device access in Finder, Home Sharing; AMPDevices.framework, AMPSharing.framework; launchd services: com.apple.AMPDeviceDiscoveryAgent, com.apple.AMPDevicesAgent, com.apple.amp.mediasharingd
24 AMP Asynchronous Multiprocessing; performance and power-efficiency cores on Apple Silicon
25 AMS Apple Media Services; formerly the iTunes stores and media services: App Stores, Apple Music, Apple TV, iCloud media library, Apple Podcasts, Podcast sync, Books Store, Books sync; AppleMediaServices.framework; server: phobos.apple.com
26 AMX Apple Matrix Extension; ARM instruction set extension for matrix operations
27 ANE Apple Neural Engine, hardware accelerator for neural network operations; ANECompiler.framework, ANEServices.framework; launchd service: com.apple.aned
28 Anisette Anisette two-factor authentication creates security codes on trusted devices using TOTP, probably using Circle keys, checked by HSA; AuthKit.framework; launchd service: com.apple.akd two-factor authentication creates security codes on trusted devices using TOTP, probably using Circle keys, checked by HSA; AuthKit.framework; launchd service: com.apple.akd
29 AOP Always On Processor, part of Apple SoCs, runs RTKit as operating system
30 AOS AOS Apple Online Services? historical name for iCloud Apple Online Services? historical name for iCloud
31 Apache built-in web server; command line tool: apachectl
32 APFS APFS Apple File System; copy-on-write file system with support for volume space-sharing, per-file encryption, and snapshots Apple File System; copy-on-write file system with support for volume space-sharing, per-file encryption, and snapshots
33 APNS APNS Apple Push Notification service, server infrastructure for remote push notifications over a single connection, clients subscribe to push topics, can be authenticated by app (remote notifications), device (Find My …), or Apple ID login (DSID); credentials in apsd keychain; launchd service: com.apple.apsd; server: push.apple.com Apple Push Notification service, server infrastructure for remote push notifications over a single connection, clients subscribe to push topics, can be authenticated by app (remote notifications), device (Find My …), or Apple ID login (DSID); credentials in apsd keychain; launchd service: com.apple.apsd; server: push.apple.com
34 App Nap App Nap quiescence detection for applications and corresponding self-demotion in scheduler parameters, implemented within the application by frameworks, listens for occlusion notifications from WindowServer quiescence detection for applications and corresponding self-demotion in scheduler parameters, implemented within application frameworks and RunningBoard, listens for occlusion notifications from WindowServer
35 App Sandbox App Sandbox Seatbelt-based sandbox for apps; /System/Library/Sandbox/Profiles/application.sb; enabled with com.apple.security.app-sandbox entitlement; launchd service: com.apple.secinitd Seatbelt-based sandbox for apps; /System/Library/Sandbox/Profiles/application.sb; enabled with com.apple.security.app-sandbox entitlement; launchd service: com.apple.secinitd
36 APT AppleCare Adaptive Picture Timing? ProMotion; dynamic screen updates with 120Hz base frequency extended warranty; NewDeviceOutreach.framework; launchd service: com.apple.ndoagent
37 APT Adaptive Picture Timing? ProMotion; dynamic screen updates with 120Hz base frequency; AppleDisplayTCONControl.framework
38 ASL ASL Apple System Logger, superseded by Unified Logging; /etc/asl; stored in /var/log/asl; launchd service: com.apple.syslogd; command line tool: syslog Apple System Logger, superseded by Unified Logging; /etc/asl; stored in /var/log/asl; launchd service: com.apple.syslogd; command line tool: syslog
39 ASR ASR Apple Software Restore; restore entire volumes from sources like disk images (HDI, SIU), also restores based on APFS snapshots and snapshot deltas; command line tool: asr Apple Software Restore; restore entire volumes from sources like disk images (HDI, SIU), also restores based on APFS snapshots and snapshot deltas; command line tool: asr
40 Assertions Assertions power state management allowing applications to prevent sleeping; launchd service: com.apple.powerd; command line tools: caffeinate, pmset power state management allowing applications to prevent sleeping; launchd service: com.apple.powerd; command line tools: caffeinate, pmset
41 Assessment Assessment checking of System Policy; term also used for school exam apps that lock the device checking of System Policy; term also used for AAC
42 Asset Cache Asset Cache discretionary caching server for Mobile Assets, Packages, iOS updates, App Store content, ODR, MMCS data; launchd services: com.apple.AssetCache.builtin, com.apple.AssetCacheLocatorService, com.apple.AssetCacheManagerService, com.apple.AssetCacheTetheratorService; command line tools: AssetCacheLocatorUtil, AssetCacheManagerUtil, AssetCacheTetheratorUtil discretionary caching server for Mobile Assets, Packages, iOS updates, App Store content, ODR, MMCS data; launchd services: com.apple.AssetCache.builtin, com.apple.AssetCacheLocatorService, com.apple.AssetCacheManagerService, com.apple.AssetCacheTetheratorService; command line tools: AssetCacheLocatorUtil, AssetCacheManagerUtil, AssetCacheTetheratorUtil
43 Assistant Assistant Siri; dictation and semantic understanding, Intent is communicated to and enacted on the client, uses TTS; /System/Library/Assistant, AssistantServices.framework; server: *.siri.apple.com Siri; dictation and semantic understanding, Intent is communicated to and enacted on the client, uses TTS for output, Snippets to embed mini UIs into responses; /System/Library/Assistant, /System/Library/Snippets, AssistantServices.framework; server: *.siri.apple.com
44 ATS ATS App Transport Security, sandbox mechanism only allowing TLS-secured connections App Transport Security, sandbox mechanism only allowing TLS-secured connections
45 ATSUI ATSUI Apple Type Services for Unicode Imaging; rendering engine superseded by CoreText.framework, font management; ApplicationServices.framework/ATS.framework; launchd service: com.apple.xtyped (fontd); command line tools: atsutil Apple Type Services for Unicode Imaging; rendering engine superseded by CoreText.framework, font management; ApplicationServices.framework/ATS.framework; launchd service: com.apple.xtyped (fontd); command line tools: atsutil
46 ATT ATT App Tracking Transparency; apps declare user tracking on app store App Tracking Transparency; apps declare user tracking on app store
47 Attestation cryptographic proof of a genuine SEP; used for web authentication and app attestation; DeviceCheck.framework; SEP responds to challenge using hardware-key (GID, PKA), online service verifies; used to pair Touch ID keyboards, used to pair RemoteXPC channel?
48 Authorization Authorization discretionary access control policies for high-level services; similar to PAM; policy stored in /var/db/auth.db discretionary access control policies for high-level services; similar to PAM; policy stored in /var/db/auth.db
49 Avatar Avatar Memoji; AvatarKit.framework Memoji and Animoji (face tracking); AvatarKit.framework
50 AVB AVB Audio Video Bridging, low-latency audio over Ethernet; launchd service: com.apple.avbdeviced; command line tool: avbdiagnose, avbutil Audio Video Bridging, low-latency audio over Ethernet; launchd service: com.apple.avbdeviced; command line tool: avbdiagnose, avbutil
51 AWD AWD Apple Wireless Diagnostics, sends system telemetry to Apple; CoreAnalytics.framework, WirelessDiagnostics.framework; launchd services: com.apple.awdd, com.apple.analyticsd Apple Wireless Diagnostics, sends system telemetry to Apple; CoreAnalytics.framework, WirelessDiagnostics.framework; launchd services: com.apple.awdd, com.apple.analyticsd
52 AWDL AWDL Apple Wireless Direct Link; secondary WiFi interface that runs in parallel to an active WiFi access point connection, similar to WiFi Direct (p2p interface), uses a randomized MAC, used for peer-to-peer networking: AirDrop, AirPlay; DeviceToDeviceManager.framework Apple Wireless Direct Link; secondary WiFi interface that runs in parallel to an active WiFi access point connection, similar to WiFi Direct (p2p interface), uses a randomized MAC, used for peer-to-peer networking: AirDrop, AirPlay; DeviceToDeviceManager.framework
53 Bezel Bezel on-screen overlays for hardware volume buttons, screen brightness, Bluetooth HID, and others; /Library/Application Support/Apple/BezelServices, launchd services: com.apple.loginwindow, com.apple.OSDUIHelper on-screen overlays for hardware volume buttons, screen brightness, Bluetooth HID, and others; /Library/Application Support/Apple/BezelServices, launchd services: com.apple.loginwindow, com.apple.OSDUIHelper
54 Bifrost emergency satellite connectivity; /System/Library/LocationBundles/Bifrost.bundle
55 Biome CloudKit-based datastream and sync engine; BiomeStreams.framework, BiomeSync.framework; launchd services: com.apple.BiomeAgent, com.apple.biomesyncd
56 Blast Door sandboxed sanitization process for untrusted iMessage input; BlastDoor.framework
57 BOM BOM Bill of Materials; format to store contents of installer Packages; command line tool: lsbom Bill of Materials; format to store contents of installer Packages; command line tool: lsbom
58 Bonjour Bonjour mDNS; launchd service: com.apple.mDNSResponder.reloaded; command line tool: dns-sd mDNS; launchd service: com.apple.mDNSResponder.reloaded; command line tool: dns-sd
59 Boot Cache Boot Cache disk cache pre-heating at boot time with typically loaded applications; /var/db/BootCaches; launchd service: com.apple.warmd disk cache pre-heating at boot time with typically loaded applications; /var/db/BootCaches; launchd service: com.apple.warmd
60 Boot Policy Boot Policy decides by signature check which OSes can be booted; boot-time equivalent for System Policy, configurable by SEP on Apple Silicon Macs, enforced by iBoot; command line tools: bputil, kmutil (to enroll custom kernels) decides by signature check which OSes can be booted, boot-time equivalent for System Policy; LocalPolicy stores user settings, configurable from 1TR, stored by SEP, enforced by iBoot; command line tools: bputil, kmutil (to enroll custom kernels)
61 BPR BPR Boot Progress Register; set-only flags to track boot mode (normal, DFU, recovery), part of Keybag class key derivation within SEP, so passcode-protected keys are inaccessible in DFU and recovery Boot Progress Register; set-only flags to track boot mode (normal, DFU, recovery), part of Keybag class key derivation within SEP, so passcode-protected keys are inaccessible in DFU and recovery
62 Bridge Bridge T2 ARM CPU in Intel Macs to drive Touch Bar and Boot Policy; runs bridgeOS, a derivative of watchOS; boots the platform and the Intel CPU, communication from macOS uses RemoteXPC, which uses HTTP/2 over a USB-Ethernet interface; launchd service: com.apple.multiversed, com.apple.remoted; /System/Library/MultiversePlugins; command line tool: remotectl T2 ARM CPU in Intel Macs to drive Touch Bar and Boot Policy; runs bridgeOS, a derivative of watchOS; boots the platform and the Intel CPU, communication from macOS uses RemoteXPC; launchd service: com.apple.multiversed; /System/Library/MultiversePlugins
63 Brook hand washing encouragement on watch; BrookServices.framework
64 Bulletin Board Bulletin Board application push notification management, aggregates local and remote push notifications; BulletinBoard.framework application push notification management, aggregates local and remote push notifications; BulletinBoard.framework
65 Cache Delete Cache Delete cleanup for various caches; /System/Library/CacheDelete; launchd service: com.apple.cache_delete (deleted) cleanup for various caches; /System/Library/CacheDelete; launchd service: com.apple.cache_delete (deleted)
66 CAML CAML Core Animation Markup Language; XML file format for layers, shapes and animations Core Animation Markup Language; XML file format for layers, shapes and animations
67 Carousel Carousel derivative of SpringBoard for Watch home screen, watch face, and notification center derivative of SpringBoard for Watch home screen, watch face, and notification center
68 Celestial Celestial media streaming used by ReplayKit for game broadcasts; Celestial.framework media streaming used by ReplayKit for game broadcasts; Celestial.framework
69 Certificates Certificates validity checked using OCSP stapling, locally installed CRLs, and transparency logs; /System/Library/Security/Certificates.bundle; /var/db/crls; launchd services: com.apple.trustd, com.apple.trustd.agent, com.apple.ocspd; command line tool: crlrefresh validity checked using CRLs, OCSP stapling, and transparency logs; /System/Library/Security/Certificates.bundle; launchd services: com.apple.trustd, com.apple.trustd.agent, com.apple.ocspd; command line tool: crlrefresh
70 Circle Chamois cryptographic primitive to exchange public keys of all trusted devices of one user, signed by all Circle peers; iCloud identity keypair as an additional Circle peer, triggers countersigning from all trusted devices, private key synced across all trusted devices, new devices can pull this key from Secure Backup to join the Circle; used by CKKS; KeychainCircle.framework; command line tools: tpctl, otctl (Octagon trust is newer?) Stage Manager
71 CKKS CHIP CloudKit Key Sync, end-to-end secure syncing for credentials, seeded by Circle, transferred items stored ephemerally using OTR protocol; currently includes ApplePay, AutoUnlock, CreditCards, DevicePairing, Engram, Health, Home, Manatee, SOS, WiFi and other keys; launchd service: com.apple.secd; command line tool: ckksctl Connected Home over IP; Matter; integrated into HomeKit; CHIPPlugin.framework
72 Classroom Circle launchd service: com.apple.studentd cryptographic primitive to exchange public keys of trusted devices of a user, signed by Circle peers; iCloud identity added as additional Circle peer, private key synced across all trusted devices, new devices can pull this key from Secure Backup to join the Circle; per-device Circles stored in CKKS for two-factor accounts (Octagon); KeychainCircle.framework; command line tools: tpctl, otctl (Octagon)
73 Cloud Pairing CKKS part of Alloy, Bluetooth out-of-band pairing over iCloud for Continuity; launchd service: com.apple.cloudpaird CloudKit Key Sync, end-to-end secure syncing for credentials, seeded by Circle; currently includes ApplePay, AutoUnlock, CreditCards, DevicePairing, Engram, Health, Home, Manatee, SOS, WiFi and other keys; launchd service: com.apple.secd; command line tool: ckksctl
74 Clarity customizable accessibility mode for simplified UI; ClarityFoundation.framework
75 Classroom school teachers can create assignments for student iPads and track progress in Schoolwork app; ClassKit.framework; launchd service: com.apple.studentd
76 Cloud Pairing part of Alloy, Bluetooth out-of-band pairing over iCloud for Continuity; launchd service: com.apple.BTServer.cloudpairing (cloudpaird)
77 CMAS CMAS Commerial Mobile Alert System, now known as Wireless Emergency Alerts (WEA) Commerial Mobile Alert System, now known as Wireless Emergency Alerts (WEA)
78 Commpage Commpage user-mapped kernel data, like vdso/vsyscall on Linux; mapped at 0x7fffffe00000 user-mapped kernel data, like vdso/vsyscall on Linux; mapped at 0x7fffffe00000
79 Communications Filter Communications Filter recipient blocking for iMessage, FaceTime, Mail; launchd service: com.apple.cmfsyncagent recipient blocking for iMessage, FaceTime, Mail; launchd service: com.apple.cmfsyncagent
80 Companion Companion iPhone that is paired with Watch; communication uses Alloy over Bluetooth iPhone that is paired with Watch; communication uses Alloy over IPsec over Bluetooth
81 Continuity Continuity umbrella term for Handoff, Sidecar, SMS relay, Universal Clipboard, Watch unlock, WiFi call relay and others; SMS relay works by proxying to iMessage, other services use Alloy umbrella term for Handoff, Sidecar, SMS relay, Universal Clipboard, Watch unlock, WiFi call relay and others; SMS relay works by proxying to iMessage, other services use Alloy
82 Control Center icons in menu/status bar and Bento Box controls UI, gradually replaces SystemUIServer on macOS; handles incoming AirPlay content; launchd services: com.apple.controlcenter, com.apple.SystemUIServer.agent
83 CPML CPML CorePrediction Machine Learning; CPMLBestShim.framework CorePrediction Machine Learning; CPMLBestShim.framework
84 CRD CRD Conference Room Display; Apple TV mode Conference Room Display; Apple TV mode
85 CSR Cryptex Code Security/Signing Restrictions/Requirements? also called System Integrity Protection (SIP) or rootless mode; collection of kernel-level security restrictions regarding file system modification, unsigned Kexts, Taskport access, NVRAM access, DTrace; /System/Library/Sandbox/rootless.conf; command line tool: csrutil, rootless-init Cryptographically sealed Extension of SSV, mount-invisible extension of the root volume, allows lightweight updates as part of Rapid Security Response; /System/Cryptexes (mountpoint), /System/Volumes/Preboot/*/cryptex1/current/*.dmg (disk images)
86 CTK CSR Crypto Token Kit; smart card management, also for the secure element on iOS? launchd service: com.apple.ctkd; command line tool: sc_auth Configurable Security Restrictions; XNU subsystem that is the basis for SIP
87 CTRR CTK Configurable Text Read-only Region; ARM CPU register to downgrade actual permissions of memory pages; used for JIT protection and by AMFI to freeze user code after checking Crypto Token Kit; smart card management, also for the Secure Element on iOS? launchd service: com.apple.ctkd; command line tool: sc_auth
88 CTS CTS Centralized Task Scheduling; execution of DAS tasks; /System/Library/UserEventPlugins/com.apple.cts.plugin Centralized Task Scheduling; execution of DAS tasks; /System/Library/UserEventPlugins/com.apple.cts.plugin
89 CVMS CVMS Core VM Server/Service? compilation of GPU shaders; launchd service: com.apple.cvmsServ Core VM Server/Service? compilation of GPU shaders; launchd service: com.apple.cvmsServ
90 DAAP DAAP Digital Audio Access Protocol; used by Home Sharing (with Rapport token) and by the Remote app to control Apple TV (with pairing token); payload unencrypted; DAAPKit.framework; Bonjour services: _atc._tcp, _home-sharing._tcp, _mediaremotetv._tcp, _touch-able._tcp Digital Audio Access Protocol; used by Home Sharing (with Rapport token) and by the Remote app to control Apple TV (with pairing token); payload unencrypted; DAAPKit.framework; Bonjour services: _atc._tcp, _home-sharing._tcp, _mediaremotetv._tcp, _touch-able._tcp
91 Daily Briefing Siri giving an overview of information for the day; SiriDailyBriefingInternal.framework
92 DART DMA Address Relocation Table; IOMMU implementation in Apple silicon, positioned in front of every DMA-capable co-processor and peripheral, offers sub-page protection; SART: streaming variant for high-throughput devices (like NVMe)
93 DAS DAS Duet Activity Scheduler; scheduling policy engine behind NSBackgroundActivityScheduler and XPC activities; /System/Library/DuetActivityScheduler; launchd service: com.apple.dasd Duet Activity Scheduler; scheduling policy engine behind NSBackgroundActivityScheduler and XPC activities; /System/Library/DuetActivityScheduler; launchd service: com.apple.dasd
94 Data Detectors Data Detectors text analysis to highlight phone numbers, street addresses, and the like; DataDetectors.framework text analysis to highlight phone numbers, street addresses, and the like; DataDetectors.framework
95 DataVaults Data Vault directories with the UF_DATAVAULT special flag; read access limited under CSR directories with the UF_DATAVAULT special flag; CSR limits access to one application
96 DAV DAV Distributed Authoring and Versioning; network protocol on top of HTTP for syncing calendars (CalDAV), contacts (CardDAV), and formerly also bookmarks (BookmarkDAV) Distributed Authoring and Versioning; network protocol on top of HTTP for syncing calendars (CalDAV), contacts (CardDAV), and formerly also bookmarks (BookmarkDAV)
97 DCIM DCP Digital Camera Images; DCIMServices.framework Display Co-Processor
98 DEP DEP Device Enrollment Program; devices check in with Apple during Setup Assistant to query for their enrollment status, retrieve MDM server URL to fetch initial configuration profile Device Enrollment Program; devices check in with Apple during Setup Assistant to query for their enrollment status, retrieve MDM server URL to fetch initial configuration profile
99 Developer Mode enables launching of self-compiled apps in iOS, rough equivalent to System Policy; command line tool: devmodectl
100 DFR DFR Dynamic Function Row?, TouchBar; /System/Library/CoreServices/ControlStrip.app; DFRFoundation.framework Dynamic Function Row?, TouchBar; /System/Library/CoreServices/ControlStrip.app; DFRFoundation.framework
101 DFU DFU Device Firmware Update; special boot mode where iOS has not booted and the system can be installed over the Lightning connection Device Firmware Update; special boot mode where iOS has not booted and the system can be installed over the Lightning connection
102 Differential Privacy Differential Privacy crowdsourcing without user tracking; privacy budget for management of anonymity set; used for keyboard words, emoji, Spotlight searches, Parsec deep links, HealthKit usage, Safari telemetry; /System/Library/DifferentialPrivacy; stored in /var/db/DifferentialPrivacy; launchd service: com.apple.dprivacyd crowdsourcing without user tracking; privacy budget for management of anonymity set; used for keyboard words, emoji, Spotlight searches, Parsec deep links, HealthKit usage, Safari telemetry; /System/Library/DifferentialPrivacy; stored in /var/db/DifferentialPrivacy; launchd service: com.apple.dprivacyd
103 Digital Separation safety check feature to inhibit sharing relationships; DigitalSeparation.framework
104 DND DND Do Not Disturb Do Not Disturb
105 DSID DSID Destination Signaling Identifier, unique ID for IDS login on a specific device Destination Signaling Identifier, unique ID for IDS login on a specific device
106 DTrace DTrace system-wide tracing infrastructure, command line tools: dtrace, *.d, dappprof, dapptrace, dtruss, errinfo, execsnoop, fddist, fs_usage, imptrace, iopattern, iopending, iosnoop, iotop, lastwords, latency, opensnoop, plockstat, rwsnoop, sampleproc, sc_usage, topsyscall, topsysproc system-wide tracing infrastructure, command line tools: dtrace, *.d, dappprof, dapptrace, dtruss, errinfo, execsnoop, fddist, fs_usage, imptrace, iopattern, iopending, iosnoop, iotop, lastwords, latency, opensnoop, plockstat, rwsnoop, sampleproc, sc_usage, topsyscall, topsysproc
107 Duet Duet telemetry collection engine for system and user events, forecasting by machine learning, backend for DAS, Proactive, Relevance, Screen Time, thermal and battery management; /System/Library/DuetKnowledgeBase; CoreDuet.framework, CoreKnowledge.framework, CorePrediction.framework; launchd services: com.apple.coreduetd, com.apple.knowledge-agent telemetry collection engine for system and user events, forecasting by machine learning, backend for DAS, Proactive, Relevance, Screen Time, thermal and battery management; /System/Library/DuetKnowledgeBase; CoreDuet.framework, CoreKnowledge.framework, CorePrediction.framework; launchd services: com.apple.coreduetd, com.apple.knowledge-agent
108 Dyld Shared Cache Dyld Shared Cache dynamic linker cache, stores all system libraries in prelinked form, original library files are removed; /System/Library/dyld; command line tool: update_dyld_shared_cache dynamic linker cache, stores all system libraries in prelinked form, original library files are removed; /System/Volumes/Preboot/Cryptexes/OS/System/Library/dyld; command line tools: dyld_info, dyld_usage, update_dyld_shared_cache
109 EAS EAS Exchange Active Sync; network protocol for accessing Microsoft Exchange servers Exchange Active Sync; network protocol for accessing Microsoft Exchange servers
110 EDR Extended Dynamic Range; rendering with transfer function extending beyond sRGB white; implemented natively on XDR displays and by backlight modulation on others; HDRProcessing.framework
111 Energy Impact Energy Impact unitless metric for per-application energy consumption, machine-specific coefficients; /usr/share/pmenergy, /usr/share/kpep; launchd services: com.apple.sysmond, com.apple.thermald; command line tool: powermetrics unitless metric for per-application energy consumption, machine-specific coefficients; /usr/share/pmenergy, /usr/share/kpep; launchd services: com.apple.sysmond, com.apple.thermald; command line tool: powermetrics
112 Engram Engram Messages in iCloud; devices store received iMessages in CloudKit; Engram.framework Messages in iCloud; devices store received iMessages in CloudKit; Engram.framework
113 Entitlements Entitlements capability-like attributes bound to executables by code signing; some entitlements like App Sandbox restrict ambient authority, some gradually relieve those restrictions (using Seatbelt), some services or system calls grant privilege based on caller entitlements capability-like attributes bound to executables by code signing; some entitlements like App Sandbox restrict ambient authority, some gradually relieve those restrictions (using Seatbelt), some services or system calls grant privilege based on caller entitlements
114 ESS ESS IDS user directory, public key distribution for iMessage and CloudKit sharing, uses Transparency; server: *.ess.apple.com; launchd service: com.apple.identityservicesd IDS user directory, public key distribution for iMessage and CloudKit sharing, uses Transparency; server: *.ess.apple.com; launchd service: com.apple.identityservicesd
Event Monitor simple rules engine for running commands on various systen events; apparently not used by default; /etc/emond.d, /var/db/emondClients; launchd service: com.apple.emond
115 FaceTime FaceTime video calls, employs the ICE (establishing peer-to-peer connection), STUN (session credential exchange) and SRTP (encrypted media streaming) protocols; FTServices.framework; launchd services: com.apple.videoconference.camera (avconferenced) video calls, employs the ICE (establishing peer-to-peer connection), STUN (session credential exchange) and SRTP (encrypted media streaming) protocols; FTServices.framework; launchd services: com.apple.videoconference.camera (avconferenced)
116 FairPlay FairPlay DRM system used by app and media stores; CoreADI.framework, CoreFP.framework, CoreLSKD.framework; launchd services: com.apple.adid, com.apple.fairplayd (invoked by kernel through host special port 17), com.apple.lskdd; credentials stored in /var/db/fpsd DRM system used by app and media stores; CoreADI.framework, CoreFP.framework, CoreLSKD.framework; launchd services: com.apple.adid, com.apple.fairplayd (invoked by kernel through host special port 17), com.apple.lskdd; credentials stored in /var/db/fpsd
117 Family Circle Family Circle Family Sharing; launchd services: com.apple.familycircled, com.apple.askpermissiond Family Sharing; launchd services: com.apple.familycircled, com.apple.askpermissiond
118 FDE FDE Full Disk Encryption, FileVault; command line tool: fdesetup, sysadminctl Full Disk Encryption, FileVault; command line tool: fdesetup, sysadminctl
119 FDR FDR Factory Data/Device Reset? ensures that no downgrades are performed? servers: skl.apple.com, gg.apple.com; /System/Library/FDR Factory Data/Device Reset? ensures that no downgrades are performed? servers: skl.apple.com, gg.apple.com; /System/Library/FDR
120 Feldspar Feldspar Apple News; Silex.framework Apple News; Silex.framework
121 FiDES FiDES Fi? Distributed Evaluation Service? ingests and aggregates Differential Privacy data for unlinkability? used for emoji, Suggestions, Dictation; /System/Library/DistributedEvaluation; DistributedEvaluation.framework; server: fides-pol.apple.com Fi? Distributed Evaluation Service? aggregates Differential Privacy data for unlinkability? maybe private federated learning? used for emoji, Suggestions, Dictation; /System/Library/DistributedEvaluation; DistributedEvaluation.framework; server: fides-pol.apple.com
122 Find My … File Provider location sharing by explicitly querying devices remotely or collateral beacon detection using Search Party; launchd service: com.apple.icloud.fmfd (find my friends) infrastructure and extension system for syncing with cloud providers; placeholder files based on SF_DATALESS attribute in APFS; FileProvider.framework; locally stored in ~/Library/CloudStorage; command line tool: fileproviderctl
123 Find My … location sharing by explicitly querying devices remotely or collateral beacon detection using Search Party; FMCore.framework, FMF.framework; launchd service: com.apple.icloud.fmfd (find my friends)
124 Firmlink Firmlink bi-directional non-symbolic link between the read-only system volume and the data volume, additional symlinks and mountpoints in the root directory are virtually allocated; /usr/share/firmlinks, /etc/synthetic.conf bi-directional non-symbolic link between the read-only system volume and the data volume, additional symlinks and mountpoints in the root directory are virtually allocated; /usr/share/firmlinks, /etc/synthetic.conf
125 Focus restriction modes for notification presentation; focus filters for in-app display restrictions, communicat by Intents; Focus.framework, DoNotDisturb.framework; local settings in ~/Library/DoNotDisturb
126 FollowUp FollowUp user interaction for Secure Backup wrapping with device passcode, CoreFollowUp.framework; launchd service: com.apple.followupd user interaction for Secure Backup wrapping with device passcode, CoreFollowUp.framework; launchd service: com.apple.followupd
127 FoundationDB FoundationDB fundamental iCloud storage database, marketed as CloudKit, separated into containers; records, blobs, and large asset storage with MMCS, server-side continuous queries can trigger push notifications, user management by IDS, sharing between users; PCS keys used for hierarchical zone, record, and asset encryption; CloudKitDaemon.framework; launchd service: com.apple.cloudd; locally stored in ~/Library/Caches/CloudKit, ~/Library/Containers/*/Data/CloudKit fundamental iCloud storage database, marketed as CloudKit, separated into containers; records, blobs, and large asset storage with MMCS, server-side continuous queries can trigger push notifications, user management by IDS, sharing between users; PCS keys used for hierarchical zone, record, and asset encryption; CloudKitDaemon.framework; launchd service: com.apple.cloudd; locally stored in ~/Library/Caches/CloudKit, ~/Library/Containers/*/Data/CloudKit; command line tool: cktool
128 FUD FPR Firmware Update Daemon; /var/db/fud; launchd service: com.apple.MobileAccessoryUpdater Fast Permission Restrictions; Apple CPU registers to downgrade (old APRRs do bitmasking) or remap (SPRRs since M1) actual permissions of memory pages (the CTRR region) per thread; used for JIT protection and by AMFI to freeze user code after checking
129 FUD Firmware Update Daemon; /var/db/fud; launchd service: com.apple.accessoryupdaterd
130 GID group ID key, shared across all devices of the same SoC generation, derived keys are used to prove device type over the network, only accessible by SEP
131 Gizmo Gizmo Apple Watch; watch settings managed by Companion; /Applications/Bridge.app, /System/Library/BridgeManifests Apple Watch; watch settings managed by Companion; /Applications/Bridge.app, /System/Library/BridgeManifests
132 Group Activities SharePlay; sharing of media content and programmatic state over FaceTime calls; GroupActivities.framework, CopresenceCore.framework; launchd service: com.apple.telephonyutilities.callservicesd
133 GSS GSS Generic Security Service; part of Kerberos; GSS.framework; launchd service: com.apple.gssd (invoked by kernel through host special port 19); command line tool: gsstool Generic Security Service; part of Kerberos; GSS.framework; launchd service: com.apple.gssd (invoked by kernel through host special port 19); command line tool: gsstool
134 GXF Guarded Execution Feature/Fault, additional exception levels on Apple Silicon, lateral to the usual exception levels; page tables remain the same, but interpretation of permission bits changes by way of FPR, genter and gexit instructions; implements lightweight intra-address-space protection contexts
135 HAP HAP Home Automation Protocol; CoreHAP.framework Home Automation Protocol; CoreHAP.framework
136 HDA HDA High Definition Audio; HDAInterface.framework High Definition Audio; HDAInterface.framework
137 HDI HDI Hard Disk Image; command line tool: hdiutil Hard Disk Image; command line tool: hdiutil
HDR High Dynamic Range; video with wide-range transfer function; HDRProcessing.framework
138 HeadBoard HeadBoard derivative of SpringBoard for tvOS home screen; /Applications/HeadBoard.app, /Applications/PineBoard.app derivative of SpringBoard for tvOS home screen; /Applications/HeadBoard.app, /Applications/PineBoard.app
139 HLS HLS HTTP Live Streaming HTTP Live Streaming
140 HSA HSA Hardware Security Architecture; version 1 used for two-step verification, SOS with iCSC; version 2 for two-factor authentication, CKKS and Secure Backup with iCDP Hardware Security Architecture; version 1 used for two-step verification, SOS with iCSC; version 2 for two-factor authentication, CKKS and Secure Backup with iCDP
141 HSM HSM Hardware Security Module; HSM fleet runs escrow service for Secure Backup; public keys for authenticating the HSM services in /System/Library/Security/Certificates.bundle/Contents/Resources/AppleESCertificates.plist Hardware Security Module; HSM fleet runs escrow service for Secure Backup
142 Hyperion Hyperion iCloud Photos, uses CloudKit; launchd service: com.apple.cloudphotod; command line tool: cpldiagnose iCloud Photos, uses CloudKit; launchd service: com.apple.cloudphotod; command line tool: cpldiagnose
143 IAP IAP iPod Accessory Protocol; IAP.framework iPod Accessory Protocol; IAP.framework
144 iBoot iBoot second boot loader stage after UEFI (macOS) or boot ROM (iOS); DFU mode is implemented here; /System/Library/CoreServices/boot.efi boot loader stage after boot ROM or UEFI (macOS on Intel); intermediate Low-Level Bootloader (LLB); DFU mode is implemented here; /System/Library/CoreServices/boot.efi
145 iCDP iCDP iCloud Data Protection, codename for a set of enhancements to iCloud privacy: device passcodes used as iCSC for Secure Backup, root keys for CKKS-enabled services only synced between devices and not stored at Apple; launchd service: com.apple.cdpd iCloud Data Protection, codename for a set of enhancements to iCloud privacy: device passcodes used as iCSC for Secure Backup, root keys for CKKS-enabled services only synced between devices and not stored at Apple; launchd service: com.apple.cdpd
146 iCloud iCloud umbrella term for a conglomerate of services, consists of FoundationDB containers with PCS views for key management, supported by CKKS; uses IDS and APNS; some services under the iCloud name are actually served by the iTunes conglomerate or by IMAP or DAV umbrella term for a conglomerate of services, consists of FoundationDB containers with PCS views for key management, supported by CKKS; uses IDS and APNS; some services under the iCloud name are actually served by AMS, IMAP, or DAV
147 iCSC iCSC iCloud Security Code, credential wrapping for Secure Backup, previously used a separate code, with HSA2/iCDP uses device passcodes iCloud Security Code, credential wrapping for Secure Backup, previously used a separate code, with HSA2/iCDP uses device passcodes
148 IDAM IDAM Inter-Device Audio and MIDI; audio connection between devices Inter-Device Audio and MIDI; audio connection between devices
149 IDS IDS Identity Service, also IDMS, Apple ID identity management for all of Apple’s online services; APNS topics for signaling and messaging, see also Alloy, ESS, FaceTime, iMessage; authentication to services with Kerberos Identity Service, also IDMS, Apple ID identity management for all of Apple’s online services; APNS topics for signaling and messaging, see also Alloy, ESS, FaceTime, iMessage; authentication to services with Kerberos
150 IM IDV Instant Messaging; usually means iMessage and FaceTime, formerly also XMPP Identity Verification? Touch ID and Face ID; /System/Library/AccessibilityBundles/CoreIDVUI.axbundle
151 Intent IM use-case-driven interaction with 3rd-party apps from a host app; used for Siri, Maps, Widgets (configuration); extension points: com.apple.intents-service, com.apple.intents-ui-service Instant Messaging; usually means iMessage and FaceTime
152 IMG4 boot files (Mach-O binaries or configuration data) with ASN.1 signature, contains RemotePolicy certificate constraints to restrict Boot Policy evaluation
153 Intent use-case-driven interaction with 3rd-party apps from a host app; used for Siri, Maps, Shortcuts, Widgets (configuration); definition file or programmatically using AppIntents.framework; command line tool: appintentsmetadataprocessor (Xcode extracts Intent definition at compile time); extension points: com.apple.intents-service, com.apple.intents-ui-service
154 IOKit IOKit device driver subsystem for in-kernel and DriverKit drivers, command line tool: ioreg device driver subsystem for in-kernel and DriverKit drivers, command line tool: ioreg
155 Ironwood Ironwood dictation, customized on server with selected user data (contacts, app names, music titles, HomeKit names, Siri Shortcut phrases), not tied to Apple ID; server: guzzoni.apple.com dictation, customized on server with selected user data (contacts, app names, music titles, HomeKit names, Siri Shortcut phrases), not tied to Apple ID; SpeechRecognitionCore.framework; server: guzzoni.apple.com
156 ISP ISP Image Signal Processor; camera imaging circuit in iPhones Image Signal Processor; camera imaging circuit in iPhones
157 ITML ITML iTunes Markup Language; metdata tagging for media services; ITMLKit.framework iTunes Markup Language; metdata tagging for media services; ITMLKit.framework
158 ITP ITP Intelligent Tracking Prevention, cross-site tracking defenses in Safari, statistics and user interaction classify sites, cookies are partitioned and access is restricted Intelligent Tracking Prevention, cross-site tracking defenses in Safari, statistics and user interaction classify sites, cookies are partitioned and access is restricted
159 iTunes JARVIS old umbrella term for a conglomerate of media services: App Stores, Apple Music, Apple TV, iCloud media library, Apple Podcasts, Podcast sync, Books Store, Books sync; server: phobos.apple.com Just A Rather Very Intelligent Scheduler, Mesos cluster manager for Siri, iCloud, AMS
160 JARVIS Jellyfish Just A Rather Very Intelligent Scheduler, Mesos cluster manager for Siri, iCloud, iTunes Animoji; /Applications/Jellyfish.app
161 Jellyfish Jetsam Animoji reclaiming of purgeable memory and termination of apps during memory pressure
Jetsam reclaiming of purgeable memory and terminatable apps during memory pressure; see TAL
162 JSC JSC JavaScript Core; JavaScriptCore.framework; command line tool: jsc JavaScript Core; JavaScriptCore.framework; command line tool: jsc
163 Kalamata codename for the transition from x86 to ARM-based Apple Silicon
164 Kerberos Kerberos single-sign-on mechanism; Heimdal.framework; command line tools: kinit, ktutil single-sign-on mechanism; Heimdal.framework; command line tools: kinit, ktutil
165 Kext Kext kernel extension mechanism, loaded at boot time as part of a Kext Collection; /Library/Extensions, /Library/StagedExtensions (for user approval), /System/Library/Extensions; command line tool: kextutil (manages deprecated runtime loading) kernel extension mechanism, loaded at boot time as part of a Kext Collection; /Library/Extensions, /Library/StagedExtensions (for user approval), /System/Library/Extensions; command line tool: kextutil (manages deprecated runtime loading)
166 Kext Collection Kext Collection prelinked sets of kernel extensions; /System/Library/KernelCollections (for boot and system kexts), /Library/KernelCollections (for auxiliary third-party kexts); the latter is only loaded at a lower-security Boot Policy; launchd service: com.apple.kernelmanagerd (invoked by kernel through host special port 15); command line tool: kmutil prelinked sets of kernel extensions; /System/Library/KernelCollections (for boot and system kexts), /Library/KernelCollections (for auxiliary third-party kexts); the latter is only loaded at a lower-security Boot Policy; launchd service: com.apple.kernelmanagerd (invoked by kernel through host special port 15); command line tool: kmutil
167 Keybag Keybag storage of protection class keys for Keychain and filesystem, protected by SEP with passcode and lockout; stored in user.kb; launchd services: com.apple.mobile.keybagd, com.apple.securityd_service, com.apple.secd storage of protection class keys for Keychain and filesystem, protected by SEP using SKP; stored in user.kb; launchd services: com.apple.mobile.keybagd, com.apple.securityd_service, com.apple.secd
168 Keychain Keychain storage for credentials; launchd service: com.apple.securityd; command line tools: certtool, security, systemkeychain storage for credentials; launchd service: com.apple.securityd; command line tools: certtool, security, systemkeychain
169 KIP KIP Kernel Integrity Protection, locking of physical memory pages to prevent changes to kernel Kernel Integrity Protection, locking of physical memory pages to prevent changes to kernel
170 Launch Services Launch Services management for applications, uses Spotlight to update cached info; launchd services: com.apple.coreservices.launchservicesd, com.apple.lsd; CoreServices.framework/LaunchServices.framework; command line tools: lsappinfo, lsregister management for application launches, association of UTIs to apps, uses Spotlight to update cached info; launchd services: com.apple.coreservices.launchservicesd, com.apple.lsd; CoreServices.framework/LaunchServices.framework; command line tools: lsappinfo, lsregister
171 Live Files user mode filesystems, currently FAT, ExFAT, NTFS on external storage; UserFS.framework, UVFSXPCService.framework; launchd service: com.apple.filesystems.userfsd
172 Liverpool Liverpool PCS codename for CloudKit PCS codename for CloudKit
173 LKDC LKDC Local Key Distribution Center, Kerberos on client machines Local Key Distribution Center, Kerberos on client machines
174 LSM LSM Latent Semantic Mapping, text analysis, used for spam filtering, command line tool: lsm Latent Semantic Mapping, text analysis, used for spam filtering, command line tool: lsm
175 Mac Buddy Mac Buddy historic name for Setup Assistant historic name for Setup Assistant
176 MAC Policy MAC Policy Mandatory Access Control subsystem in XNU, based on TrustedBSD, implements policy hooks for restricted kernel operations; current policies: AMFI, Seatbelt, Quarantine, CSR Mandatory Access Control subsystem in XNU, based on TrustedBSD, implements policy hooks for restricted kernel operations; current policies: AMFI, Seatbelt, Quarantine, CSR
177 Machine Learning Machine Learning Vision.framework, Espresso.framework, Futhark.framework, PhotoAnalysis.framework Vision.framework, Espresso.framework, Futhark.framework, PhotoAnalysis.framework; used for Live Text and Visual Lookup; launchd service: com.apple.mediaanalysisd
178 Madrid Madrid iMessage; /System/Library/Messages iMessage; /System/Library/Messages
179 Manatee Manatee PCS key for some CloudKit containers are synced via CKKS, so data is unreadable to Apple (credential management codenames: Plesio, Stingray, Cuttlefish) PCS key for some CloudKit containers are synced via CKKS, so data is unreadable to Apple (credential management codenames: Plesio, Stingray, Cuttlefish)
180 Mandrake emergency siren on Apple Watch Ultra; /Applications/Mandrake.app
181 Mangrove Mangrove transfering UI tiles over XPC; Mangrove.framework, IOSurface.framework transfering UI tiles over XPC; Mangrove.framework, IOSurface.framework
182 Marco Marco Marco.framework, something about IDS and communication (iMessage, Calls), logging? Marco.framework, something about IDS and communication (iMessage, Calls), logging?
183 Marklar Marklar codename from the PowerPC era for the port to x86, served the transition to Intel CPUs codename from the PowerPC era for the port to x86, served the transition to Intel CPUs
184 Marzipan Marzipan Catalyst; port of iOS frameworks to macOS, Catalyst apps are iOS apps with additional API to adapt macOS UI idioms; /System/iOSSupport; integration using UIKit system process; launchd service: com.apple.uikitsystemapp Catalyst; port of iOS frameworks to macOS, Catalyst apps are iOS apps with additional API to adapt macOS UI idioms; /System/iOSSupport; integration using UIKit system process; launchd service: com.apple.uikitsystemapp; input remapping by /Library/Apple/Library/Bundles/InputAlternatives.bundle
185 MCX MCX Managed Client for OS X, preference management for settings from configuration profiles, /Library/Managed Preferences, command line tools: mcxquery, mcxrefresh Managed Client for OS X, preference management for settings from configuration profiles, /Library/Managed Preferences, command line tools: mcxquery, mcxrefresh
186 MDM MDM Mobile Device Management; server software to manage fleets of iOS and macOS devices; uses configuration profiles to manage preferences; ConfigurationProfiles.framework Mobile Device Management; server software to manage fleets of iOS and macOS devices; uses configuration profiles to manage preferences; ConfigurationProfiles.framework
187 MDS MDS Module Directory Services, ancient part of the old security APIs (CSDA, CSSM) Module Directory Services, ancient part of the old security APIs (CSDA, CSSM)
188 Memory Debugging Memory Debugging uses Taskport; command line tools: heap, leaks, malloc_history, stringdups, vmmap uses Taskport; command line tools: heap, leaks, malloc_history, stringdups, vmmap
189 Mesa Mesa Touch ID; /Library/Catacomb; /var/db/bkad.db Touch ID; /Library/Catacomb; /var/db/bkad.db
190 Metadata Metadata Spotlight; file indexing on macOS; CoreServices.framework/Metadata.framework, CoreServices.framework/SearchKit.framework; stored in .Spotlight-V100; launchd service: com.apple.metadata.mds; command line tools: mddiagnose, mdfind, mdimport, mdls, mdutil; in addition to auto-indexing, apps can explicitly register searchable items; CoreSpotlight.framework; launchd service: com.apple.corespotlightd Spotlight; file indexing on macOS; CoreServices.framework/Metadata.framework, CoreServices.framework/SearchKit.framework; stored in .Spotlight-V100; launchd service: com.apple.metadata.mds; command line tools: mddiagnose, mdfind, mdimport, mdls, mdutil; in addition to auto-indexing, apps can explicitly register searchable items; CoreSpotlight.framework; launchd service: com.apple.corespotlightd
191 MMCS MMCS MobileMe Chunk Storage, used by iCloud, splits blobs into chunks and stores them at Amazon/Google with convergent encryption; MMCS.framework MobileMe Chunk Storage, used by iCloud, splits blobs into chunks and stores them at Apple/AWS/GCP with convergent encryption (content hash as key); MMCS.framework
192 Mobile Mobile prefix for iOS prefix for iOS
193 Mobile Assets Mobile Assets demand-downloaded system components like fonts, dictionaries, linguistic data; stored in /System/Library/Assets; launchd services: com.apple.languageassetd (language-dependent assets), com.apple.mobileassetd; server: mesu.apple.com demand-downloaded system components like fonts, dictionaries, linguistic data; stored in /System/Library/Assets; launchd services: com.apple.languageassetd (language-dependent assets), com.apple.mobileassetd; server: mesu.apple.com
194 Mobile Device Mobile Device connectivity to iOS devices over USB or WiFi (AirTrafficHost) for syning, development, and debugging; MobileDevice.framework; launchd service: com.apple.usbmuxd; Bonjour service: _apple-mobdev2._tcp connectivity to iOS devices over USB or WiFi (AirTrafficHost) for syning, development, and debugging; MobileDevice.framework; launchd service: com.apple.usbmuxd; Bonjour service: _apple-mobdev2._tcp
197 MRT MRT Malware Removal Tool; /Library/Apple/System/Library/CoreServices/MRT.app Malware Removal Tool; /Library/Apple/System/Library/CoreServices/MRT.app
198 Multipeer Connectivity Multipeer Connectivity ad-hoc networking; Bonjour for discovery; WiFi, AWDL, Bluetooth, or Ethernet as transport; optional encryption and certificate-based authentication; MultipeerConnectivity.framework ad-hoc networking; Bonjour for discovery; WiFi, AWDL, Bluetooth, or Ethernet as transport; optional encryption and certificate-based authentication; MultipeerConnectivity.framework
199 Nano Nano prefix for watchOS prefix for watchOS
200 Neural Engine Nearby Interaction hardware accelerator for neural network operations; ANECompiler.framework, ANEServices.framework; launchd service: com.apple.aned proximity-based interaction between devices; proximity measured using ultra wideband or derived from other technologies; used for Universal Control; NearbyInteraction.framework, Proximity.framework; launchd service: com.apple.nearbyd
201 Newton Newton fall detection on watchOS fall detection on watchOS
202 NLP NLP Natural Language Processing; NLP.framework; related to mecabra libraries, a linguistic engine for Chinese and Japanese; /usr/share/mecabra, /usr/share/tokenizer Natural Language Processing; NLP.framework; related to mecabra libraries, a linguistic engine for Chinese and Japanese; /usr/share/mecabra, /usr/share/tokenizer
203 Notarization Notarization app security scan by Apple; cryptographic proof stapled to code signature, tested at launch by System Policy; for non-notarized apps sends code hash to Apple; command line tools: altool, stapler app security scan by Apple; cryptographic proof stapled to code signature, tested at launch by System Policy; for non-notarized apps sends code hash to Apple; command line tools: notarytool, altool, stapler
204 Noticeboard Noticeboard User Notifications for Software Update and App Store, Noticeboard.framework; launchd services: com.apple.noticeboard.state (nbstated), com.apple.noticeboard.agent (nbagent) User Notifications for Software Update and App Store, Noticeboard.framework; launchd services: com.apple.noticeboard.state (nbstated), com.apple.noticeboard.agent (nbagent)
205 Notifications Notifications system notification bus, unrelated to the local/remote push notifications; launchd service: com.apple.notifyd, com.apple.kuncd (invoked by kernel through host special port 10); command line tool: notifyutil; complemented by framework-level notification system (CFNotification, NSNotification); launchd services: com.apple.distnoted.xpc.daemon, com.apple.distnoted.xpc.agent system notification bus, unrelated to the local/remote push notifications; launchd service: com.apple.notifyd, com.apple.kuncd (invoked by kernel through host special port 10); command line tool: notifyutil; complemented by framework-level notification system (CFNotification, NSNotification); launchd services: com.apple.distnoted.xpc.daemon, com.apple.distnoted.xpc.agent
206 NSP NSP Network Service Proxy; per-app VPN and proxy settings; launchd service: com.apple.networkserviceproxy Network Service Proxy; per-app VPN and proxy settings, implements Private Relay; launchd service: com.apple.networkserviceproxy
207 OAH OAH Rosetta Rosetta; ahead-of-time compiler for Intel code on Apple Silicon; /usr/libexec/rosetta
208 ODR ODR On-Demand Resources; loaded from App Store; launchd service: com.apple.appstored On-Demand Resources; loaded from App Store; launchd service: com.apple.appstored
209 Onboarding Onboarding data protection splash screen shown by service-connected apps; /System/Library/OnBoardingBundles; OnBoardingKit.framework data protection splash screen shown by service-connected apps; /System/Library/OnBoardingBundles; OnBoardingKit.framework
210 Open Directory Open Directory directory service for user, group, and machine management; plugin-based to use different backend stores (LDAP, Active Directory), local accounts in /private/var/db/dslocal; launchd service: com.apple.opendirectoryd; command line tools: dscacheutil, dscl, dsconfigad, dsconfigldap, dseditgroup, dsenableroot, dserr, dsexport, dsimport, dsmemberutil, odutil directory service for user, group, and machine management; plugin-based to use different backend stores (LDAP, Active Directory), local accounts in /private/var/db/dslocal; launchd service: com.apple.opendirectoryd; command line tools: dscacheutil, dscl, dsconfigad, dsconfigldap, dseditgroup, dsenableroot, dserr, dsexport, dsimport, dsmemberutil, odutil
213 OTUT OTUT One-Time Unlock Token; security mechanism to allow keybag unwrapping after updates One-Time Unlock Token; security mechanism to allow keybag unwrapping after updates
214 PAC PAC Pointer Authentication Codes; pointers signed in unused bits to prevent ROP attacks Pointer Authentication Codes; pointers signed in unused bits to prevent ROP attacks
215 Packages Packages unit of software installation; command line tools: pkgutil, installer, softwareupdate; launchd services: com.apple.softwareupdated, com.apple.bootinstalld, com.apple.installd, com.apple.system_installd, com.apple.uninstalld; /var/db/softwareupdate, /Library/Apple/System/Library/Receipts (system), /System/Library/Receipts (read-only), /private/var/db/receipts (App Store) unit of software installation; command line tools: pkgutil, installer, softwareupdate; launchd services: com.apple.softwareupdated, com.apple.bootinstalld, com.apple.installd, com.apple.system_installd, com.apple.uninstalld; /var/db/softwareupdate, /Library/Apple/System/Library/Receipts (system), /System/Library/Receipts (read-only), /private/var/db/receipts (App Store)
216 Packet Filter network traffic filtering subsystem from OpenBSD; command line tool: pfctl
217 Parsec Parsec Spotlight web results and searching of crowdsourced User Activity deep links; server: *.smoot.apple.com; launchd services: com.apple.parsecd, com.apple.parsec-fbf (Feedback Flush to Differential Privacy) Spotlight web results and searching of crowdsourced User Activity deep links; server: *.smoot.apple.com; launchd services: com.apple.parsecd, com.apple.parsec-fbf (Feedback Flush to Differential Privacy)
218 Pasteboard Password Breach storage for cut, copy, and paste; launchd service: com.apple.pboard; command line tools: pbcopy, pbpaste monitoring of Keychain passwords against a breach database; round-robin matching in fixed-size batches, local match against common leaks, remote match using hash prefix; launchd service: com.apple.Safari.passwordbreachd
219 Pasteboard storage for cut, copy, and paste; type of content remembered as UTI; launchd service: com.apple.pboard; command line tools: pbcopy, pbpaste
220 PCS PCS Protected Cloud Storage; key management for separate iCloud storage compartments (PCS calls them views), each can contain FoundationDB plus bulk data stored by MMCS; see also iCDP, CKKS, Manatee; ProtectedCloudStorage.framework; /System/Library/Preferences/ProtectedCloudStorage; command line tool: pcsstatus Protected Cloud Storage; key management for separate iCloud storage compartments (PCS calls them views), each can contain FoundationDB plus bulk data stored by MMCS; see also iCDP, CKKS, Manatee; ProtectedCloudStorage.framework; /System/Library/Preferences/ProtectedCloudStorage; command line tool: pcsstatus
221 PCSC PCSC Personal Computer Smart Card; PCSC.framework, uses CTK Personal Computer Smart Card; PCSC.framework, uses CTK
222 PDE PDE Print Dialog Extension; old name, not a proper Extension Print Dialog Extension; old name, not a proper Extension
223 Pegasus Pegasus picture-in-picture video playback; Pegasus.framework (iOS), PIP.framework (macOS) meaning 1: picture-in-picture video playback; Pegasus.framework (iOS), PIP.framework (macOS); meaning 2: online search query engine for visual lookup; PegasusKit.framework
224 Pepper Pepper UI elements for Watch home screen and Chat, like Quickboard (canned replies), Animoji; PepperUICore.framework UI elements for Watch home screen and Chat, like Quickboard (canned replies), Animoji; PepperUICore.framework
225 Persona Persona separation of sub-user-identities, like when using a private and managed Apple account; PersonaKit.framework; ~/Library/Personas; /System/Library/UserManagement separation of sub-user-identities, like when using a private and managed Apple account; PersonaKit.framework; ~/Library/Personas; /System/Library/UserManagement; command line tool: umtool
226 PHASE Physical Audio Spatialization Engine; 3D sound rendering engine; Apple devices map audio sources (even mono and stereo) to virtual speakers in a 3D sound stage, which is simulated by the physical speakers via a head-related transfer function; PHASE.framework
227 Piano Mover Piano Mover Mail Drop; bulk mail attachments transfered over PCS; not to be confused with storage for iMessage attachments, which uses a CloudKit container Mail Drop; bulk mail attachments transfered over PCS; not to be confused with storage for iMessage attachments, which uses a CloudKit container
228 Plugin Plugin Extensions, XPC services bundled with apps or frameworks, discovery by Launch Services; launchd service: com.apple.pluginkit.pkd; command line tool: pluginkit Extensions, XPC services bundled with apps or frameworks, discovery by Launch Services; launchd service: com.apple.pluginkit.pkd; command line tool: pluginkit
229 PMP PMP Port Mapping Protocol; Apple alternative to UPnP, Bonjour service: _acp-sync._tcp Port Mapping Protocol; Apple alternative to UPnP, Bonjour service: _acp-sync._tcp
230 Poster iPhone lock screen; PosterBoard.framework, PosterKit.framework
231 PowerUI PowerUI battery management like smart charge and power save, learns from Duet and other data; PowerUI.framework; /var/db/PowerUI; launchd service: com.apple.PowerUIAgent battery management like smart charge and power save, learns from Duet and other data; PowerUI.framework; /var/db/PowerUI; launchd service: com.apple.PowerUIAgent
232 Preferences Preferences storage for user-configurable settings; launchd services: com.apple.cfprefsd.xpc.daemon, com.apple.cfprefsd.xpc.agent; stored in Library/Preferences, command line tool: defaults; interaction with Synced Defaults per /System/Library/DefaultsConfigurations storage for user-configurable settings; launchd services: com.apple.cfprefsd.xpc.daemon, com.apple.cfprefsd.xpc.agent; stored in Library/Preferences, command line tool: defaults; interaction with Synced Defaults per /System/Library/DefaultsConfigurations
233 Private Relay two-hop onion routing with one entry and one exit node; Apple operates entry, third-party services operate exit nodes; QUIC for payload, ODoH for DNS, approximate IP geolocation via Waldo; authentication via Attestation, propagated to proxys using RSA blind signatures
234 Proactive Proactive umbrella term for suggestions and completions based on Duet forecasting and User Activity context, also marketed as Siri features; PersonalizationPortrait.framework umbrella term for suggestions and completions based on Duet forecasting and User Activity context, also marketed as Siri features; PersonalizationPortrait.framework
235 QoS Classes QoS Classes inheritable property for Activities; semantic priorities, influences scheduling parameters; initially set at user-level, priority inheritance within GCD queues and across XPC in kernel? inheritable property for Activities; semantic priorities, influences scheduling parameters; initially set at user-level, priority inheritance within GCD queues and across XPC in kernel?
236 Quagga Quagga framework for QR and barcode decoding; Quagga.framework framework for QR and barcode decoding; Quagga.framework
237 Quick Action extension type for quick interaction with foreign content within a host app; extension points: com.apple.services, com.apple.ui-services
238 Quick Look Quick Look file preview and thumbnail generation; comand line tool: qlmanage file preview and thumbnail generation; comand line tool: qlmanage
239 RAOP RAOP Remote Audio Output Protocol, AirPlay; Bonjour service: _raop._tcp Remote Audio Output Protocol, AirPlay; Bonjour service: _raop._tcp
240 Rapport Rapport device pairing by proximity using Alloy, with PIN entry, or using iCloud; once paired, devices can access services; used for HomeKit, HomePod, AirPlay, Home Sharing, SideCar; Rapport.framework; launchd service: com.apple.rapportd; Bonjour service: _companion-link._tcp device pairing by proximity using Alloy, with PIN entry, or using iCloud; once paired, devices can access services; used for HomeKit, HomePod, AirPlay, Home Sharing, SideCar; Rapport.framework; launchd service: com.apple.rapportd; Bonjour service: _companion-link._tcp
241 Recents Recents recently used items (not files) in various applications, synced with Synced Defaults; CoreRecents.framework, /System/Library/Recents; launchd service: com.apple.recentsd recently used items (not files) in various applications, synced with Synced Defaults; CoreRecents.framework, /System/Library/Recents; launchd service: com.apple.recentsd
242 Relevance Engine Relevance Engine backend for Siri suggestions (for example of Siri Shortcuts), Siri watch face, Widget smart stacks; consumes Duet knowledge and app-provided timelines; /System/Library/RelevanceEngine; launchd service: com.apple.relevanced backend for Siri suggestions (for example of Siri Shortcuts), Widget smart stacks (also Siri watch face); consumes Duet knowledge and app-provided timelines with relevance hints; /System/Library/RelevanceEngine; launchd service: com.apple.relevanced
243 Remote Pairing Mobile Device pairing without wired connection; RemotePairingDevice.framework; Bonjour services: _remotepairing._tcp, _remotepairing-manual-pairing._tcp
244 RemoteXPC connection to a non-SoC-integrated SEP like Bridge; uses HTTP/2 over a network interface, Bridge connected over USB, secured using Attestation; RemoteServiceDiscovery.framework, TrustedAccessory.framework; launchd service: com.apple.remoted, com.apple.tracd; command line tool: remotectl
245 Revisions Revisions document autosave and auto-versioning; stored in .DocumentRevisions-V100; GenerationalStorage.framework; launchd service: com.apple.revisiond document autosave and auto-versioning; stored in .DocumentRevisions-V100; GenerationalStorage.framework; launchd service: com.apple.revisiond
246 Routine Routine frequently visited locations on iOS, interacts with Duet; launchd service: com.apple.routined frequently visited locations on iOS, interacts with Duet; launchd service: com.apple.routined
247 RTC RTC Real-time Telemetry and Crash reporting; RTCReporting.framework; launchd service: com.apple.rtcreportingd Real-time Telemetry and Crash reporting; RTCReporting.framework; launchd service: com.apple.rtcreportingd
248 RTKit operating system used on Apple Silicon for firmware of co-processors
249 RunningBoard runtime management of apps, paradigm: app as service process invoked by system, check-in by frameworks, handles process assertions (frontmost app, see App Nap), memory pressure (see Jetsam) and compute resources (GPU), replacement for TAL?; launchd service: com.apple.runningboardd; /System/Library/LifecyclePolicy, /System/Library/RunningBoard
250 SBPL SBPL Sandbox Profile Language; a TinyScheme-based embedded DSL for Seatbelt profiles Sandbox Profile Language; a TinyScheme-based embedded DSL for Seatbelt profiles
251 SCIP SCIP System Coprocessor Integrity Protection; like KIP, but for SEP, ISP, Motion coprocessor System Coprocessor Integrity Protection; like KIP, but for SEP, ISP, Motion coprocessor
252 Screen Reader Screen Reader VoiceOver and Braille; /System/Library/ScreenReader; ScreenReader.framework VoiceOver and Braille; /System/Library/ScreenReader; ScreenReader.framework
253 Screen Time Screen Time digital wellbeing and parental controls system, uses Device Management as policy engine, self-enforced within the application by frameworks; launchd services: com.apple.ScreenTimeAgent, com.apple.dmd digital wellbeing and parental controls system, uses Device Management as policy engine, self-enforced within the application by frameworks; DeviceActivity.framework, ManagedSettings.framework, FamilyControls.framework; launchd services: com.apple.ScreenTimeAgent, com.apple.dmd
254 SDB SDB SQL Database; CoreSDB.framework, used by iCloud communication SQL Database; CoreSDB.framework, used by iCloud communication
255 Search Party Search Party portion of Find My service for offline devices; devices emit public part of rotating key pair via Bluetooth LE, other devices encrypt current location with this key and send to Apple, private key shared over CloudKit portion of Find My service for offline devices; devices emit public part of rotating key pair via Bluetooth LE, other devices encrypt current location with this key and send to Apple, private key shared over CloudKit
256 Seatbelt Seatbelt process sandbox by filtering system calls; /System/Library/Sandbox/Profiles, /usr/share/sandbox; profiles written in a SBPL; command line tool: sandbox-exec; launchd service: com.apple.sandboxd (invoked by kernel through host special port 14 for logging) process sandbox by filtering system calls; profiles written in SBPL; /System/Library/Sandbox/Profiles, /usr/share/sandbox; default file access policy asks for TCC confirmation before access to folders with user data (like Documents) is allowed; command line tool: sandbox-exec; launchd service: com.apple.sandboxd (invoked by kernel through host special port 14 for logging)
257 Secure Backup Secure Backup escrow part of CKKS; escrow key individually wrapped with passcodes of trusted devices, stored in HSM to prevent brute forcing, uses SRP so passcodes are not visible to iCloud, limited number of recovery attempts; protocol called Lakitu, uses FollowUp; launchd service: com.apple.SecureBackupDaemon; CloudServices.framework escrow part of CKKS; escrow key individually wrapped with passcodes of trusted devices, stored in HSM to prevent brute forcing, uses SRP so passcodes are not visible to iCloud, limited number of recovery attempts; protocol called Lakitu, uses FollowUp; launchd service: com.apple.SecureBackupDaemon (com.apple.sbd); CloudServices.framework
258 SEP SEP Secure Enclave Processor; dedicated ARM core for security services, runs L4/Darbat, inline encryption to DRAM, factory-paired channels to Touch ID/Face ID hardware and Secure Element; SEP can use but not read device UID key, usage restricted to ROM code Secure Enclave Processor; dedicated ARM core for security services, runs L4/Darbat-based sepOS, inline encryption to DRAM, manages AES keys in storage DMA engine, factory-paired channels to Touch ID/Face ID hardware, Secure Element, Neural Engine; SEP can use but not read UID and GID keys; credential verification performed by hardware lockbox with retry count enforcement
259 Sequoia translation; downloadable language models can run on-device; /Applications/SequoiaTranslator.app, Translation.framework
260 Seymour Apple Fitness+; workout videos integrated with Watch sensors; SeymourCore.framework
261 SF Symbols scalable UI symbols; rendered with various color treatments; SFSymbols.framework
262 Sharing Sharing umbrella term for wireless proximity services: AirDrop, Continuity, Instant Hotspot, WiFi sharing; used by loginwindow for Watch unlock; Sharing.framework; launchd service: com.apple.sharingd; also serves connection sharing and remote disk umbrella term for wireless proximity services: AirDrop, Continuity, Instant Hotspot, WiFi sharing; used by loginwindow for Watch unlock; Sharing.framework; launchd service: com.apple.sharingd; also serves connection sharing and remote disk
263 Shazam audio (especially music) recognition service; ShazamKit.framework; launchd service: com.apple.shazamd; command line tool: shazam
264 Shoebox Shoebox Passbook Passbook
265 Sidecar Sidecar using iPhone/iPad as Mac accessory: camera for photos and scanning, annotations, external display over low-latency WiFi (llw interface) using avconferenced encoding; SidecarCore.framework; launchd services: com.apple.sidecar-display-agent (SidecarDisplayAgent), com.apple.sidecar-relay (SidecarRelay) using iPhone/iPad as Mac accessory: external camera and microphone (ContinuityCapture), camera for photos and scanning (DocumentCamera.framework), external display over low-latency WiFi (llw interface) using avconferenced encoding; SidecarCore.framework; launchd services: com.apple.sidecar-display-agent (SidecarDisplayAgent), com.apple.sidecar-relay (SidecarRelay)
266 Signpost Signpost telemetry API to report points of interest in code; launchd service: com.apple.signpost.signpost_reporter telemetry API to report points of interest in code; launchd service: com.apple.signpost.signpost_reporter
267 Simulator Simulator running an iOS/tvOS/watchOS personality on macOS, uses sandboxing and a separate Mach bootstrap namespace for container-like isolation, command line tool: simctl running an iOS/tvOS/watchOS personality on macOS, uses sandboxing and a separate Mach bootstrap namespace for container-like isolation; installable simulators as disk images in /Library/Developer/CoreSimulator/Images; command line tool: simctl
268 SIP System Integrity Protection or rootless mode; collection of kernel-level security restrictions regarding file system modification, unsigned Kexts, Taskport access, NVRAM access, DTrace; /System/Library/Sandbox/rootless.conf; command line tool: csrutil, rootless-init
269 Site Association signed files in .well-known directory on websites; equivalent to Entitlements for websites, associates domains with app IDs for Universal Links; command line tool: swcutil
270 SKP Sealed Key Protection; measurement of system state (boot chain IMG4 manifests, BPR, Boot Policy data, UID key, user passcode) to derive Keybag keys
271 SKS SKS Secure Key Store; handling of keybag keys within the SEP Secure Key Store; handling of keybag keys within the SEP
272 SkyLight SkyLight WindowServer; SkyLight.framework WindowServer; SkyLight.framework
273 Skywalk Skywalk network subsystem in XNU, links together actual technologies (Bluetooth, WiFi, Thunderbolt) and interfaces/tunnels; transacts in nexus (for conduits) and agent (for endpoints) objects; command line tool: skywalkctl network subsystem in XNU, links together actual technologies (Bluetooth, WiFi, Thunderbolt) and interfaces/tunnels; transacts in nexus (for conduits) and agent (for endpoints) objects; DriverKit network drivers use Skywalk; command line tool: skywalkctl
274 SLC System-Level Cache, architectural feature of Apple Silicon; cache located within SoC at controllers for external DRAM, serves all compute units and stages transfers between them
275 Social Gaming Social Gaming Game Center; multiplayer gaming services on top of CloudKit, shared storage and low-latency multicast for multiplayer sessions; launchd service: com.apple.gamed Game Center; multiplayer gaming services on top of CloudKit, shared storage and low-latency multicast for multiplayer sessions; launchd service: com.apple.gamed
276 Sock Puppet Sock Puppet Watch interaction that requires Companion device Watch interaction that requires Companion device
277 SOS SOS Secure Object Sync; syncing backend for iCloud Keychain, not to be confused with the emergency call feature; transferred items previously staged in Synced Defaults, now uses CKKS; launchd services: com.apple.secd (access to local keychain), com.apple.security.cloudkeychainproxy3 (connects to Synced Defaults), com.apple.security.keychain-circle-notification Secure Object Sync; syncing backend for iCloud Keychain, not to be confused with the emergency call feature; transferred items previously staged in Synced Defaults, for two-factor accounts in CKKS; launchd services: com.apple.secd (access to local keychain), com.apple.security.cloudkeychainproxy3 (connects to Synced Defaults), com.apple.security.keychain-circle-notification
278 SPI SPI System Private Interface; /System/Library/PrivateFrameworks System Private Interface; /System/Library/PrivateFrameworks
279 SpringBoard SpringBoard iOS home screen; like Dock (Launchpad, Mission Control, desktop picture), Control Center, SystemUIServer (menu extras icons), loginwindow (lock screen), and WindowServer (compositor) on macOS; /System/Library/CoreServices/SpringBoard.app, /Applications/PreBoard.app, BaseBoard.framework, FrontBoard.framework, SplashBoard.framework, /System/Library/RunningBoard; launchd service: com.apple.backboardd (compositor) iOS home screen; like Dock (Launchpad, Mission Control, desktop picture), Control Center, SystemUIServer (menu extras icons), loginwindow (lock screen), and WindowServer (compositor) on macOS; /System/Library/CoreServices/SpringBoard.app, /Applications/PreBoard.app, BaseBoard.framework, FrontBoard.framework, SplashBoard.framework; launchd service: com.apple.backboardd (compositor)
280 SPRR Shadow Permission Remap Register? feature of Apple Silicon to dynamically reintepret page permissions
281 SRP SRP Secure Remote Password; standard cryptographic protocol for proving knowledge of a secret such that attackers cannot brute-force the secret; AppleSRP.framework Secure Remote Password; standard cryptographic protocol for proving knowledge of a secret such that attackers cannot brute-force the secret; AppleSRP.framework
282 SSO SSO Single Sign-On Single Sign-On
283 SSV SSV Signed System Volume, als called Authenticated Root Volume (ARV); macOS boots from blessed read-only APFS snapshot, merkle-tree and root-hash stored in Preboot volume; modifications require disabling root authentication with csrutil from recovery, then the live filesystem can be mounted, modified, and re-blessed; command line tools: apfs_systemsnapshot, bless, csrutil Signed System Volume, als called Authenticated Root Volume (ARV); macOS boots from blessed read-only APFS snapshot, merkle-tree and root-hash stored in Preboot volume; modifications require disabling root authentication with csrutil from recovery, then the live filesystem can be mounted, modified, and re-blessed; command line tools: apfs_systemsnapshot, bless, csrutil
284 Stark Stark CarPlay CarPlay
285 Stockholm Stockholm Apple Pay; also Warsaw Secure Element in Apple SoCs, a processor running crypto protocols on keys it protects; used for Apple Pay and Car Key; related codenames: Icefall, Warsaw
286 Storage Management Storage Management freeing up disk space by managing bulky items; UI in System Information.app; StorageManagement.framework; launchd service: com.apple.diskspaced; extension point: com.apple.storagemanagement; extends Cache Delete service freeing up disk space by managing bulky items; UI in System Information.app; StorageManagement.framework; launchd service: com.apple.diskspaced; extension point: com.apple.storagemanagement; extends Cache Delete service
287 Suggestions Suggestions semantic analysis of mails and websites to suggest contacts, calendar events and the like; launchd services: com.apple.suggestd, com.apple.reversetemplated; custom JavaScript parsers in /System/Library/AssetsV2/com_apple_MobileAsset_CoreSuggestions semantic analysis of mails and websites to suggest contacts, calendar events and the like; launchd services: com.apple.suggestd, com.apple.reversetemplated; custom JavaScript parsers in /System/Library/AssetsV2/com_apple_MobileAsset_CoreSuggestions
288 Symbols Symbols debug symbols for backtraces; CoreSymbolication.framework; launchd services: com.apple.coresymbolicationd; command line tools: symbols, symbolscache debug symbols for backtraces; CoreSymbolication.framework; launchd services: com.apple.coresymbolicationd; command line tools: atos, symbols, symbolscache
289 Symptoms Symptoms network diagnostics; Symptoms.framework; /var/networkd/db/netusage.sqlite; launchd service: com.apple.symptomsd (invoked by kernel through host special port 27) network diagnostics; Symptoms.framework; /var/networkd/db/netusage.sqlite; launchd service: com.apple.symptomsd (invoked by kernel through host special port 27)
290 Synced Defaults Synced Defaults simple key-value store for applications, no user control over data; can use iCloud key-value backend (old) or Manatee container (new, marked as com.apple.kvs) as storage; launchd service: com.apple.syncdefaultsd; locally stored in ~/Library/SyncedPreferences simple key-value store for applications, no user control over data; can use iCloud key-value backend (old) or Manatee container (new, marked as com.apple.kvs) as storage; launchd service: com.apple.syncdefaultsd; locally stored in ~/Library/SyncedPreferences
291 System Configuration System Configuration SystemConfiguration.framework; launchd service: com.apple.configd; command line tool: scutil SystemConfiguration.framework; launchd service: com.apple.configd; command line tool: scutil
292 System Extension System Extension user-level components formerly in the kernel; currently either a DriverKit, Network, or Endpoint Security extension; /System/DriverKit, /System/Library/DriverExtensions; command line tool: systemextensionsctl; launchd services: com.apple.sysextd, com.apple.nesessionmanager, com.apple.endpointsecurity.endpointsecurityd user-level components formerly in the kernel; currently either a DriverKit, Network, or Endpoint Security extension; /System/DriverKit, /System/Library/DriverExtensions; command line tool: systemextensionsctl; launchd services: com.apple.sysextd, com.apple.nesessionmanager, com.apple.endpointsecurity.endpointsecurityd; command line tool: eslogger
293 System Policy System Policy Gatekeeper; policy engine for application launches and kext loading; /var/db/SystemPolicy; launchd service: com.apple.security.syspolicy (invoked by kernel through host special port 29); command line tool: spctl Gatekeeper; policy engine for application launches and kext loading, malware signatures from /Library/Apple/System/Library/CoreServices/XProtect.bundle; /var/db/SystemPolicy; launchd service: com.apple.security.syspolicy (invoked by kernel through host special port 29); command line tool: spctl
294 TAL TAL Transparent App Lifecycle; app process is started and stopped independently of the user launching and quitting app; also handles session restore across reboots; ~/Library/Saved Application State; launchd service: com.apple.talagent Transparent App Lifecycle; process for macOS apps started and stopped independently of the user launching and quitting app; also handles session restore across reboots; ~/Library/Saved Application State; launchd service: com.apple.talagent
295 Taskport Taskport Mach kernel concept for ptrace-like access to task internals; access policy implemented by daemon; launchd service: com.apple.taskgated (invoked by kernel through task special port 9); command line tool: DevToolsSecurity Mach kernel concept for ptrace-like access to task internals; access policy implemented by daemon; launchd service: com.apple.taskgated (invoked by kernel through task special port 9); command line tool: DevToolsSecurity
296 TCC TCC Transparency, Consent, and Control; user control over app access to privacy-related services (kTCCService*); TCC.framework; launchd services: com.apple.tccd, com.apple.tccd.system; command line tool: tccutil; stored in /Library/Application Support/com.apple.TCC, ~/Library/Application Support/com.apple.TCC, /var/db/locationd (for kTCCServiceLocation) Transparency, Consent, and Control; user control over app access to privacy-related services (kTCCService*); TCC.framework; launchd services: com.apple.tccd, com.apple.tccd.system; command line tool: tccutil; stored in /Library/Application Support/com.apple.TCC, ~/Library/Application Support/com.apple.TCC, /var/db/locationd (for kTCCServiceLocation)
297 Time Machine Time Machine automatic backup service, command line tools: tmdiagnose, tmutil automatic backup service, command line tools: tmdiagnose, tmutil
298 Tin Can Tin Can Walkie Talkie on watchOS Walkie Talkie on watchOS
299 Tones Tones ringtones; ToneLibrary.framework ringtones; ToneLibrary.framework
300 Tourist Translocation backend for user-visible tips and hints; launchd service: com.apple.touristd app binary copied on launch to dedicated location; initiated by Launch Services for security (prevents path traversal for apps quarantined by System Policy) or path normalization (iOS apps do not expect to be moved, but can be moved on macOS)
301 Transparency Transparency key transparency for ESS keys? Transparency.framework; launchd service: com.apple.transparencyd; server: init-kt.apple.com key transparency for ESS keys? Transparency.framework; launchd service: com.apple.transparencyd; server: init-kt.apple.com
302 TTS TSS Text To Speech, command line tool: say; /System/Library/Speech; synthesizer engines: MacinTalk (historic), Polyglot (phoneme-based?), Gryphon (current, DNN-based?) Tatsu Signing Server; online verification for firmware signatures; server: gs.apple.com
303 TTS Text To Speech, neural-network-based synthesis engine (Gryphon); command line tool: say; /System/Library/Speech, /System/Library/TTSPlugins
304 TVML TVML TV Markup Language; declarative UI language for TV apps; TVMLKit.framework TV Markup Language; declarative UI language for TV apps; TVMLKit.framework
305 Ubiquity Ubiquity iCloud Drive; uses CloudKit, codename Bladerunner; CloudDocs.framework; command line tools: fileproviderctl; launchd service: com.apple.bird (iclouddrive-agent); locally stored in ~/Library/Mobile Documents (was supposed to move to Library/CloudStorage/iCloud Drive and iclouddrivectl but this was reverted) iCloud Drive; codename Bladerunner, uses CloudKit; CloudDocs.framework; launchd service: com.apple.bird; locally stored in ~/Library/Mobile Documents (was supposed to move to Library/CloudStorage/iCloud Drive but this was reverted)
306 UID unique ID key, used as root key for cryptographic subsystems, generated during manufacturing by SEP and fused into hardware, only accessible by SEP
307 Unified Logging Unified Logging system-wide logging and Activity tracking; launchd service: com.apple.logd, com.apple.diagnosticd; command line tool: log; /dev/oslog; data stored in /var/db/diagnostics, support files in /var/db/uuidtext system-wide logging and Activity tracking; launchd service: com.apple.logd, com.apple.diagnosticd; command line tool: log; /dev/oslog; data stored in /var/db/diagnostics, support files in /var/db/uuidtext
308 User Activity USD abstraction behind deep-linking into apps with structured context data (people, places); used for Universal Links (with schema.org on websites), Handoff, Parsec, Siri Shortcuts, Proactive; UserActivity.framework; launchd service: com.apple.coreservices.useractivityd Universal Scene Description; storage format for 3D assets; /usr/lib/usd
309 User Activity abstraction for deep-linking into apps with structured context (people, places); used for Universal Links (schema.org on websites), Handoff, Parsec (app links in search), Siri Shortcuts, Quick Note (context awareness), Proactive; UserActivity.framework; launchd service: com.apple.coreservices.useractivityd
310 User Notifications User Notifications user interface for notification center; launchd service: com.apple.usernoted user interface for notification center; launchd service: com.apple.usernoted
311 UTI Uniform Type Identifiers; system for document types; file extensions and MIME types are mapped to UTIs, UTIs form a conformance graph, apps register their UTIs with Launch Services; /System/Library/CoreServices/CoreTypes.bundle; also Apple’s hardware devices are represented as UTIs
312 VA VA Video Acceleration; AppleGVA.framework, AppleVA.framework, AppleVPA.framework Video Acceleration; AppleGVA.framework, AppleVA.framework, AppleVPA.framework
313 Viceroy Viceroy video conferencing used by FaceTime and ReplayKit video conferencing used by FaceTime and ReplayKit; ViceroyTrace.framework
314 VSDB VSDB volume status database; /var/db/volinfo.database; command line tool: vsdbutil volume status database; /var/db/volinfo.database; command line tool: vsdbutil
315 Waldo Waldo VPN key management? location aware? seen in NSP, server: waldo.apple.com selects edge servers based on approximate location, part of Private Relay, seen in NSP
316 WFS WFS WebDAV File Sharing; built-in file sharing with Apache; /etc/wfs; command line tool: wfsctl WebDAV File Sharing; built-in file sharing with Apache; /etc/wfs; command line tool: wfsctl
317 Widgets Widgets content excerpt from apps; provided via a timeline of views, configuration uses Intents; extension point: com.apple.widgetkit-extension content excerpt from apps; provided via a timeline of view hierarchies, configuration uses Intents; visible on home screen, lock screen, as live activities, as watch complications; WidgetKit.framework; extension point: com.apple.widgetkit-extension
318 Willow Willow HomeKit; end-to-end-encrypted communication protocol and API for IoT-accessories; pairing with SRP using code printed on device, credential sync by CKKS, transported over Alloy, remote access using Apple TV as proxy; launchd service: com.apple.homed HomeKit; end-to-end-encrypted communication protocol and API for IoT-accessories; pairing with SRP using code printed on device, credential sync by CKKS, transported over Alloy, remote access using Apple TV as proxy; launchd service: com.apple.homed
319 xART Workflow persistent storage for SEP, used by Mesa; /System/Volumes/xarts; launchd service: com.apple.xartstorageremoted; command line tool: xartutil Shortcuts; user-programmable system-wide automation, built-in triggers cause a chain of actions to run; actions are synthesized from User Activities and Intents provided by apps; WorkflowKit.framework, ActionKit.framework; locally stored in ~/Library/Shortcuts; launchd service: com.apple.siriactionsd (voice-triggered shortcuts); command line tool: shortcuts
320 xART eXtended Anti-Replay Technology; persistent storage for SEP, used by Mesa; /System/Volumes/xarts; launchd service: com.apple.xartstorageremoted; command line tool: xartutil
321 XCS XCS Xcode Server; continuous integration server; command line tools: xcscontrol, xcsdiagnose Xcode Server; continuous integration server; command line tools: xcscontrol, xcsdiagnose