27 Commits

Author SHA1 Message Date
Michael Roitzsch
2980fbdb3e internals: update for macOS 26.3 Tahoe 2026-02-09 15:58:24 +01:00
Michael Roitzsch
00dec27c21 internals: update for macOS 26.0 Tahoe
plutil properly uses standard error, remove weird output filtering
2025-11-06 21:48:31 +01:00
Michael Roitzsch
0ce7696886 flake: adjust AMFI instructions for Apple Silicon 2025-11-06 21:48:31 +01:00
Michael Roitzsch
c2fce02d25 flake: update nixpkgs 2025-11-06 21:46:29 +01:00
Michael Roitzsch
04a302d6f0 flake: update nixpkgs
• stdenvNoCC no longer requires clearing DEVELOPER_DIR and SDKROOT
• add package builds as checks
2025-08-30 08:59:10 +02:00
Michael Roitzsch
d7fe5fd055 remember macOS defang gist in README 2025-05-15 20:50:56 +02:00
Michael Roitzsch
b67aedf6a1 switch to arm64
• my main machine is Apple Silicon now
• filter architecture in objdump as it would normally output all archs
2025-05-13 16:28:44 +02:00
Michael Roitzsch
8b7b181499 flake: move to stdenvNoCC where xcode is used 2025-05-13 11:51:14 +02:00
Michael Roitzsch
50ba2072da Makefile: de-duplicate dylibs and strings
to save space
2025-05-13 11:50:25 +02:00
Michael Roitzsch
bcfee3495c internals: update for macOS 15.4 Sequoia 2025-04-06 15:55:58 +02:00
Michael Roitzsch
9ee8532129 Makefile: collect files with ‘restricted’ flag 2025-02-06 15:50:48 +01:00
Michael Roitzsch
540c51e2ab Makefile: increase robustness
• move all checks to the very beginning to fail early
• handle simulator paths with spaces
• handle executable paths with quotes
2025-02-06 12:02:05 +01:00
Michael Roitzsch
267285f0ca flake: remove empty line 2025-02-06 12:00:43 +01:00
Michael Roitzsch
473d673639 update dsc-extractor link in README 2024-12-27 17:46:09 +01:00
Michael Roitzsch
ac261dd12c flake: update nixpkgs
stdenv now sets DEVELOPER_DIR and SDKROOT to a Nixpkgs-internal SDK,
unset if we want the platform Xcode SDK
2024-12-27 17:46:09 +01:00
Michael Roitzsch
c9193777b2 internals: update for macOS 15.2 Sequoia 2024-12-13 10:11:36 +01:00
Michael Roitzsch
58817482b7 Makefile: select last of multiple simulators
support multiple installed simulators for iOS, tvOS, watchOS
2024-12-12 12:53:54 +01:00
Michael Roitzsch
039fa246de internals: update for macOS 15.0 Sequoia 2024-09-10 13:42:16 +02:00
Michael Roitzsch
2c989cabcf Makefile: extend plist extraction
add LaunchAngels and NanoLaunchDaemons to plist extraction
2024-07-15 11:54:47 +02:00
Michael Roitzsch
d74406462a Makefile: root-only folders in simulators
/private/var/db/modelmanagerd is a new root-only folder in the simulators
2024-06-28 14:49:19 +02:00
Michael Roitzsch
bfc608e30e flake: update for Xcode 16.0 2024-06-28 14:48:17 +02:00
Michael Roitzsch
305fe81fa6 internals: add watchdog 2024-04-24 13:02:23 +02:00
Chas. J. Owens IV
9a3d767be2 Added Watchdog 2024-04-22 15:45:27 -04:00
Michael Roitzsch
ef3cb1d7aa internals: update for macOS 14.4 Sonoma 2024-03-17 11:33:06 +01:00
Michael Roitzsch
e2ae918b3f flake: update for Xcode 15.2 2024-03-17 11:32:04 +01:00
Michael Roitzsch
093a04de7f flake: cleanup 2024-01-17 19:40:03 +01:00
Michael Roitzsch
61ff7f899f flake: load snapshot-header the non-flake way
it’s a fixed version that does not participate in 'nix flake update'
2024-01-17 19:39:49 +01:00
5 changed files with 183 additions and 143 deletions

View File

@@ -1,6 +1,6 @@
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_TARGETS = db_files db_binaries db_manifests db_assets db_services
DB_TARGETS = db_files db_restricted db_binaries db_manifests db_assets db_services
CHECK_TARGETS = check_files check_binaries check_manifests check_services
.PHONY: all check view sqlite $(DB_TARGETS) $(CHECK_TARGETS)
@@ -33,7 +33,8 @@ check: internals.tsv
@$(MAKE) --silent --jobs=1 $(CHECK_TARGETS)
define VIEW
SELECT path,os FROM files;
SELECT path,os FROM files WHERE restricted IS NULL;
SELECT path,os,'restricted' FROM files WHERE restricted;
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);
@@ -56,16 +57,24 @@ DSCEXTRACTOR = $(shell nix build --no-write-lock-file --no-warn-dirty .\#dsc-ext
readlink result && rm result)/bin/dyld-shared-cache-extractor
$(DB_TARGETS)::
# evaluate helper tools to catch Nix build errors early
: $(ACEXTRACT)
: $(DSCEXTRACTOR)
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
# check presence of helper tools and other preconditions
if ! test -x $(ACEXTRACT) ; then \
printf '\033[1macextract tool unavailable\033[m\n' >&2 ; \
echo 'FAIL;' ; \
exit 1 ; \
fi
if ! test -x $(DSCEXTRACTOR) ; then \
printf '\033[1mdscextractor tool unavailable\033[m\n' >&2 ; \
echo 'FAIL;' ; \
exit 1 ; \
fi
if ! csrutil status | grep -Fq disabled ; then \
printf '\033[1mdisable SIP to get complete file information\033[m\n' >&2 ; \
echo 'FAIL;' ; \
exit 1 ; \
fi
dyld: /System/Cryptexes/OS/System/Library/dyld/dyld_shared_cache_arm64e /System/Cryptexes/OS/System/DriverKit/System/Library/dyld/dyld_shared_cache_arm64e
for i in $+ ; do $(DSCEXTRACTOR) $$i $@ ; done > /dev/null
find $@ -type f -print0 | xargs -0 chmod a+x
@@ -74,9 +83,9 @@ XCODE = $(lastword $(wildcard /Applications/Xcode.app /Applications/Xcode-beta.a
prefix = $$(case $(1) in \
(macOS) ;; \
(macOS-dyld) echo $(dir $(realpath $(firstword $(MAKEFILE_LIST))))/dyld ;; \
(iOS) echo $(wildcard /Library/Developer/CoreSimulator/Volumes/iOS_*/Library/Developer/CoreSimulator/Profiles/Runtimes/iOS*.simruntime/Contents/Resources/RuntimeRoot) ;; \
(tvOS) echo $(wildcard /Library/Developer/CoreSimulator/Volumes/tvOS_*/Library/Developer/CoreSimulator/Profiles/Runtimes/tvOS*.simruntime/Contents/Resources/RuntimeRoot) ;; \
(watchOS) echo $(wildcard /Library/Developer/CoreSimulator/Volumes/watchOS_*/Library/Developer/CoreSimulator/Profiles/Runtimes/watchOS*.simruntime/Contents/Resources/RuntimeRoot) ;; \
(iOS) echo $(lastword $(wildcard /Library/Developer/CoreSimulator/Volumes/iOS_*))/Library/Developer/CoreSimulator/Profiles/Runtimes/iOS*.simruntime/Contents/Resources/RuntimeRoot ;; \
(tvOS) echo $(lastword $(wildcard /Library/Developer/CoreSimulator/Volumes/tvOS_*))/Library/Developer/CoreSimulator/Profiles/Runtimes/tvOS*.simruntime/Contents/Resources/RuntimeRoot ;; \
(watchOS) echo $(lastword $(wildcard /Library/Developer/CoreSimulator/Volumes/watchOS_*))/Library/Developer/CoreSimulator/Profiles/Runtimes/watchOS*.simruntime/Contents/Resources/RuntimeRoot ;; \
esac)
find = \
@@ -84,9 +93,9 @@ find = \
$(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 /' ; \
find $(XCODE)/Contents/Developer $(1) | sed 's|^$(XCODE)|macOS /Applications/Xcode.app|' ; \
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)" ; $(2) find . $(1) 2> /dev/null | sed '1d;s/^\./iOS /' ; \
cd "$(call prefix,tvOS)" ; $(2) find . $(1) 2> /dev/null | sed '1d;s/^\./tvOS /' ; \
cd "$(call prefix,watchOS)" ; $(2) find . $(1) 2> /dev/null | sed '1d;s/^\./watchOS /' ; \
}
file = SELECT id, $(1) FROM files WHERE os = '$$os' AND path = '$$(echo "$$path" | sed "s/'/''/g")'
@@ -99,36 +108,38 @@ $(DB_TARGETS)::
echo 'BEGIN IMMEDIATE TRANSACTION;'
db_files:: dyld
if ! csrutil status | grep -Fq disabled ; then \
printf '\033[1mdisable SIP to get complete file information\033[m\n' >&2 ; \
echo 'FAIL;' ; \
exit 1 ; \
fi
printf '\033[1mcollecting file information...\033[m\n' >&2
echo 'DROP TABLE IF EXISTS files;'
echo 'CREATE TABLE files (id INTEGER PRIMARY KEY, os TEXT, path TEXT, executable BOOLEAN);'
echo 'CREATE TABLE files (id INTEGER PRIMARY KEY, os TEXT, path TEXT, restricted BOOLEAN, executable BOOLEAN);'
$(call find,,sudo) | sed -E "s/'/''/g;s/([^ ]*) (.*)/INSERT INTO files (os, path) VALUES('\1', '\2');/"
find $(HOME)/Library | sed "s|^$(HOME)|~|;s/'/''/g;s/.*/INSERT INTO files (os, path) VALUES('macOS', '&');/"
echo 'CREATE INDEX _files_path ON files (path);'
db_restricted:: dyld
printf '\033[1mcollecting restricted files...\033[m\n' >&2
$(call find,-flags restricted,sudo) | while read -r os path ; do \
echo "UPDATE files SET restricted = true WHERE os = '$$os' AND path = '$$(echo "$$path" | sed "s/'/''/g")' ;" ; \
done
db_binaries:: dyld
printf '\033[1mcollecting executable information...\033[m\n' >&2
echo 'DROP TABLE IF EXISTS linkages;'
echo 'DROP TABLE IF EXISTS entitlements;'
echo 'DROP TABLE IF EXISTS strings;'
echo 'CREATE TABLE linkages (id INTEGER REFERENCES files, dylib TEXT);'
echo 'CREATE TABLE linkages (id INTEGER REFERENCES files, dylib TEXT, UNIQUE (id, dylib));'
echo 'CREATE TABLE entitlements (id INTEGER REFERENCES files, plist JSON);'
echo 'CREATE TABLE strings (id INTEGER REFERENCES files, string TEXT);'
echo 'CREATE TABLE strings (id INTEGER REFERENCES files, string TEXT, UNIQUE (id, string));'
$(call find,-follow -type f -perm +111) | while read -r os path ; do \
echo "UPDATE files SET executable = true WHERE os = '$$os' AND path = '$$path';" ; \
echo "UPDATE files SET executable = true WHERE os = '$$os' AND path = '$$(echo "$$path" | sed "s/'/''/g")';" ; \
if test -r "$(call prefix,$$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,'&');|" ; \
case "$$(lipo -archs "$(call prefix,$$os)$$path")" in (*arm64e*) arch=arm64e ;; (*arm64_32*) arch=arm64_32 ;; (*arm64*) arch=arm64 ;; (*x86_64h*) arch=x86_64h ;; (*x86_64*) arch=x86_64 ;; (*) continue ;; esac ; \
objdump --arch=$$arch --macho --dylibs-used "$(call prefix,$$os)$$path" | \
sed "1d;s/^.//;s/ ([^)]*)$$//;s/'/''/g;s|.*|INSERT OR IGNORE INTO linkages $(call file,'&');|" ; \
codesign --display --xml --entitlements - "$(call prefix,$$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)$$path" | \
LANG=C sed "s/'/''/g;s|.*|INSERT INTO strings $(call file,'&');|" ; \
plutil -convert json - -o - 2> /dev/null | \
sed "/^{}/d;s/'/''/g;s|.*|INSERT INTO entitlements $(call file,json('&'));\n|" ; \
strings -n 8 "$(call prefix,$$os)$$path" 2> /dev/null | \
LANG=C sed "s/'/''/g;s|.*|INSERT OR IGNORE INTO strings $(call file,'&');|" ; \
fi ; \
done
@@ -137,8 +148,8 @@ db_manifests::
echo 'DROP TABLE IF EXISTS info;'
echo 'CREATE TABLE info (id INTEGER REFERENCES files, plist JSON);'
$(call find,-type f -name 'Info.plist') | while read -r os path ; do \
test -r "$(call prefix,$$os)$$path" && plutil -convert json "$(call prefix,$$os)$$path" -o - | \
sed "/: invalid object/d;s/'/''/g;s|.*|INSERT INTO info $(call file,json('&'));\n|" ; \
test -r "$(call prefix,$$os)$$path" && plutil -convert json "$(call prefix,$$os)$$path" -o - 2> /dev/null | \
sed "s/'/''/g;s|.*|INSERT INTO info $(call file,json('&'));\n|" ; \
done
$(call find,-type f -name 'TemplateInfo.plist') | while read -r os path ; do \
test -r "$(call prefix,$$os)$$path" && { \
@@ -148,16 +159,11 @@ db_manifests::
PlistBuddy -c 'Print Options:0:Units:Swift:Definitions:Info.plist\:NSExtension' "$(call prefix,$$os)$$path" ; \
PlistBuddy -c 'Print Options:0:Units:Swift:Definitions:Info.plist\:EXAppExtensionAttributes' "$(call prefix,$$os)$$path" ; \
echo '</dict>' ; \
} 2> /dev/null | plutil -convert json - -o - | \
sed "/Property List error:/d;s/'/''/g;s|.*|INSERT INTO info $(call file,json('&'));\n|" ; \
} 2> /dev/null | plutil -convert json - -o - 2> /dev/null | \
sed "s/'/''/g;s|.*|INSERT INTO info $(call file,json('&'));\n|" ; \
done
db_assets::
if ! test -x $(ACEXTRACT) ; then \
printf '\033[1macextract tool unavailable\033[m\n' >&2 ; \
echo 'FAIL;' ; \
exit 1 ; \
fi
printf '\033[1mcollecting asset catalog information...\033[m\n' >&2
echo 'DROP TABLE IF EXISTS assets;'
echo 'CREATE TABLE assets (id INTEGER REFERENCES files, name TEXT);'
@@ -170,8 +176,8 @@ db_services::
printf '\033[1mcollecting launchd service information...\033[m\n' >&2
echo 'DROP TABLE IF EXISTS services;'
echo 'CREATE TABLE services (id INTEGER REFERENCES files, kind TEXT, plist JSON);'
$(call find,-type f -name '*.plist' -path '*/LaunchAgents/*' -o -path '*/LaunchDaemons/*') | while read -r os path ; do \
case "$$path" in (*/LaunchAgents/*) kind=agent ;; (*/LaunchDaemons/*) kind=daemon ;; esac ; \
$(call find,-type f -name '*.plist' -path '*/LaunchAgents/*' -o -path '*/LaunchAngels/*' -o -path '*/LaunchDaemons/*' -o -path '*/NanoLaunchDaemons/*') | while read -r os path ; do \
case "$$path" in (*/LaunchAgents/*) kind=agent ;; (*/LaunchAngels/*) kind=angel ;; (*/LaunchDaemons/*) kind=daemon ;; (*/NanoLaunchDaemons/*) kind=daemon-nano ;; esac ; \
test -r "$(call prefix,$$os)$$path" && plutil -convert json "$(call prefix,$$os)$$path" -o - | \
sed "s/'/''/g;s|.*|INSERT INTO services $(call file,'$$kind'$(,)json('&'));\n|" ; \
done

View File

@@ -10,7 +10,7 @@ tools:
[**acextract**](https://github.com/bartoszj/acextract)
Unpacks asset catalogs to individual files.
[**dyld-shared-cache-util**](https://github.com/antons/dyld-shared-cache-big-sur)
[**dyld-shared-cache-extractor**](https://github.com/keith/dyld-shared-cache-extractor)
Extracts dynamic libraries from the dyld linker cache.
[**snapUtil**](https://github.com/ahl/apfs)
@@ -26,6 +26,9 @@ and checks the internals text file against this information. Collected details i
* launchd service descriptions and bundle Info.plist content
* lists of assets inside asset catalogs
To manually analyze and debug macOS, it can be helpful to temporarily [disable its security
protections](https://gist.github.com/macshome/15f995a4e849acd75caf14f2e50e7e98).
___
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.

27
flake.lock generated
View File

@@ -35,11 +35,11 @@
"dsc-extractor": {
"flake": false,
"locked": {
"lastModified": 1688099356,
"narHash": "sha256-NaPFOiPwGdwVxxZr5eRklhD41IKw8DvYoZg0kLReY5k=",
"lastModified": 1702321461,
"narHash": "sha256-bV0MesIw0lVrhNuEkfexTFhQ73EynryQskvk8egecEs=",
"owner": "keith",
"repo": "dyld-shared-cache-extractor",
"rev": "ac746c15a62f51e1ff32e4d101b5d8c70f2cb2fe",
"rev": "c28b25abf09d9affa96fc1bdcaa6d7aef1f64032",
"type": "github"
},
"original": {
@@ -50,11 +50,11 @@
},
"nixpkgs": {
"locked": {
"lastModified": 1692494774,
"narHash": "sha256-noGVoOTyZ2Kr5OFglzKYOX48cx3hggdCPbXrYMG2FDw=",
"lastModified": 1762361079,
"narHash": "sha256-lz718rr1BDpZBYk7+G8cE6wee3PiBUpn8aomG/vLLiY=",
"owner": "NixOS",
"repo": "nixpkgs",
"rev": "3476a10478587dec90acb14ec6bde0966c545cc0",
"rev": "ffcdcf99d65c61956d882df249a9be53e5902ea5",
"type": "github"
},
"original": {
@@ -68,8 +68,7 @@
"command-line": "command-line",
"dsc-extractor": "dsc-extractor",
"nixpkgs": "nixpkgs",
"snap-util": "snap-util",
"snapshot-header": "snapshot-header"
"snap-util": "snap-util"
}
},
"snap-util": {
@@ -87,18 +86,6 @@
"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",

View File

@@ -13,31 +13,28 @@
url = "github:keith/dyld-shared-cache-extractor";
flake = false;
};
snapshot-header = {
url = "https://github.com/apple/darwin-xnu/archive/refs/tags/xnu-6153.141.1.tar.gz";
flake = false;
};
snap-util = {
url = "github:ahl/apfs";
flake = false;
};
};
outputs = { self, nixpkgs, acextract, command-line, dsc-extractor, snapshot-header, snap-util }: {
packages.x86_64-darwin = let
xcode = (nixpkgs.legacyPackages.x86_64-darwin.xcodeenv.composeXcodeWrapper {
version = "15.0.1";
}).overrideAttrs (attrs: { __noChroot = true; });
outputs = { self, nixpkgs, acextract, command-line, dsc-extractor, snap-util }: {
packages.aarch64-darwin = let
xcode = nixpkgs.legacyPackages.aarch64-darwin.xcodeenv.composeXcodeWrapper {};
in {
acextract =
with import nixpkgs { system = "x86_64-darwin"; };
with nixpkgs.legacyPackages.aarch64-darwin;
let xcodeHook = makeSetupHook {
name = "xcode-hook";
propagatedBuildInputs = [ xcode ];
} "${xcbuildHook}/nix-support/setup-hook";
in stdenv.mkDerivation {
in stdenvNoCC.mkDerivation {
name = "acextract-${lib.substring 0 8 self.inputs.acextract.lastModifiedDate}";
src = acextract;
nativeBuildInputs = [ xcodeHook ];
__noChroot = true;
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";
@@ -80,22 +77,31 @@
cp Products/Release/acextract $out/bin/
'';
dontStrip = true;
__noChroot = true;
};
dsc-extractor =
with import nixpkgs { system = "x86_64-darwin"; };
with nixpkgs.legacyPackages.aarch64-darwin;
stdenv.mkDerivation {
name = "dsc-extractor-${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 {
with nixpkgs.legacyPackages.aarch64-darwin;
let snapshot-header = fetchFromGitHub {
owner = "apple";
repo = "darwin-xnu";
rev = "xnu-6153.141.1";
hash = "sha256-/2aR6n5CbUobwbxkrGqBOAhCZLwDdIsoIOcpALhAUF8=";
};
in stdenvNoCC.mkDerivation {
name = "snap-util-${lib.substring 0 8 self.inputs.snap-util.lastModifiedDate}";
src = snap-util;
nativeBuildInputs = [ xcode ];
preBuild = "NIX_CFLAGS_COMPILE='-idirafter ${snapshot-header}/bsd'";
preBuild = ''
NIX_CFLAGS_COMPILE='-idirafter ${snapshot-header}/bsd'
'';
installPhase = ''
mkdir -p $out/bin
cp snapUtil $out/bin/.snapUtil-wrapped
@@ -107,12 +113,15 @@
echo 'snapUtil requires SIP and AMFI to be disabled:'
echo ' boot recovery system'
echo ' run csrutil disable'
echo ' boot into macOS again'
echo ' run nvram boot-args=amfi_get_out_of_my_way=0x1'
echo ' reboot so boot-args is effective'
exit 1
fi
EOF
chmod a+x $out/bin/snapUtil
'';
__noChroot = true;
postFixup = ''
cat > snapUtil.entitlements <<- EOF
<?xml version="1.0" encoding="UTF-8"?>
@@ -128,8 +137,9 @@
EOF
codesign -s - --entitlement snapUtil.entitlements $out/bin/.snapUtil-wrapped
'';
__noChroot = true;
};
};
checks = self.packages;
};
}

View File

@@ -1,25 +1,27 @@
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 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
ACDC Apple Chips in Data Centers; see PCC
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
Acoustic ID song recognition and matching with Apple catalog, playback on HomePod; /System/Library/Components/AudioDSP.component
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
AFM Apple Foundation Model; pre-trained transformer and diffusion models for Greymatter, optimized for on-device use by quantization (with accuracy-recovery adapters) and palletization; command line tool: modelcatalogdump
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-Layer Firewall, launchd service: com.apple.alf (socketfilterfw)
ALF Application-Layer Firewall; implemented as a Network Extension (see System Extension); launchd service: com.apple.alf (socketfilterfw); command line tool: 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); disabled by setting amfi_get_out_of_my_way=0x1 in boot-args
AMFI Apple Mobile File Integrity, checks code integrity based on code signature, stronger enforcement with hardened runtime, validates entitlement restrictions and environment constraints (launch constraints, library constraints); 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
@@ -30,32 +32,32 @@ 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
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 Account 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 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
AppleCare extended warranty; NewDeviceOutreach.framework; launchd service: com.apple.ndoagent
APT Adaptive Picture Timing? ProMotion; dynamic screen updates with 120Hz base frequency; AppleDisplayTCONControl.framework
Ask To parental-controlled user can ask parent for exceptions; launchd service: com.apple.asktod; AskToCore.framework
Ask To parental-controlled user can ask parent for exceptions; launchd service: com.apple.asktod; AskTo.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 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 for output, Snippets to embed mini UIs into responses; /System/Library/Assistant, /System/Library/Snippets, AssistantServices.framework; server: *.siri.apple.com
Assistant Siri; speech recognition and semantic understanding, dialog management by CDM, Intent is communicated to and enacted on the client, uses TTS for speech 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 and Animoji, including pre-rendered iMessage stickers; 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
AVB Audio Video Bridging, low-latency audio over Ethernet; launchd service: com.apple.avbdeviced; command line tools: avbanalyse, avbdiagnose, avbutil
AWD Apple Wireless Diagnostics, sends system telemetry to Apple; CoreAnalytics.framework, WirelessDiagnostics.framework; launchd services: 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
Background Assets assets that an app extension loads without the app being launched; BackgroundAssets.framework; extension point: com.apple.background-asset-downloader-extension; launchd service: com.apple.backgroundassets.user
Background Assets assets that an app extension loads without the app being launched; BackgroundAssets.framework; launchd service: com.apple.backgroundassets.user
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-synced real-time event streaming and processing; widely used, primarily Avatars/People? Siri?; BiomeStreams.framework, BiomeSync.framework; launchd services: com.apple.BiomeAgent, com.apple.biomesyncd
Blast Door sandboxed sanitization process for untrusted iMessage input; BlastDoor.framework
Biome CloudKit-synced streaming and storage of events like donated and invoked Intents; semantic index to ground AI with personal context; BiomeStreams.framework, BiomeSync.framework; launchd services: com.apple.BiomeAgent, com.apple.biomesyncd; embedding vector extraction and storage: ZeoliteFramework.framework
Blast Door sandboxed sanitization process for untrusted input, used for iMessage, IDS, Telephony, media analysis; BlastDoor.framework, CTBlastDoorSupport.framework, IDSBlastDoorSupport.framework, MediaAnalysisBlastDoorSupport.framework, MessagesBlastDoorSupport.framework, TelephonyBlastDoorSupport.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
@@ -67,26 +69,30 @@ Bulletin Board application push notification management, aggregates local and re
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
CDM Continuous Dialog Manager; dialog with Siri; ContinuousDialogManagerService.framework, Marrs.framework;
Celestial media streaming used by ReplayKit for game broadcasts; Celestial.framework
CBOR Concise Binary Object Representation; JSON-inspired compact binary data serialization; CBORLibrary.framework
CDHash Code Directory Hash; a hash of hashes over the parts of a code bundle; command line tool: codesign
CDM Continuous Dialog Manager; natural dialog with Siri, MARRS for multi-modality; ContinuousDialogManagerService.framework
CEC Consumer Electronics Control; remote control for HDMI-connected devices; CoreRC.framework, IOCEC.framework
Celestial media streaming used by ReplayKit for in-app screen broadcasts; Celestial.framework; launchd service: com.apple.replayd
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; HomeKitMatter.framework
CHIP Connected Home over IP; Matter; integrated into HomeKit, can use Thread as transport layer; HomeKitMatter.framework, CoreThread.framework; launchd services: com.apple.threadradiod, com.apple.ThreadCommissionerService
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: 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
CL4 Apples variant of the L4 microkernel, derived from Pistachio/seL4 and Wombat/Darbat
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 IPsec over Bluetooth
Companion iPhone that is linked with Watch, Mac, or Apple TV; communication with Watch uses Alloy over IPsec over Bluetooth, AWDL on demand; launchd service: com.apple.companiond; Bonjour service: _companion-link._tcp
Contact Key Verification code for manual verification of iMessage keys; code identifies a long-lived account key stored in iCloud Keychain, which signs all ESS device keys
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
Continuity umbrella term for Handoff, Sidecar, iPhone Mirroring, SMS relay, Universal Clipboard, Watch unlock, WiFi call relay and others; SMS relay works by proxying to iMessage, other services use Alloy for signalling and AWDL for payload; /System/Applications/iPhone Mirroring.app, ScreenContinuityServices.framework
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
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)
Cryptex Cryptographically sealed Extension of SSV, mount-invisible overlay 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
@@ -94,6 +100,7 @@ CVMS Core VM Server/Service? compilation of GPU shaders; launchd service: com.ap
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)
Darwin Directory static store for users and groups, saves Open Directory interaction for the local case? /usr/lib/system/libsystem_darwindirectory.dylib, /System/Library/DarwinDirectory, /private/var/db/DarwinDirectory; command line tool: dddiagnose
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
Data Vault directories with the UF_DATAVAULT special flag; CSR limits access to one application
@@ -106,19 +113,22 @@ DFR Dynamic Function Row?, TouchBar; /System/Library/CoreServices/ControlStrip.a
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
DMC Device Management Client; part of MDM; DMCUtilities.framework
DMC Device Management Client; part of MDM; DMCApps.framework, DMCUtilities.framework
DMC Disk Mount Conditioner; simulates slow IO devices; command line tool: dmc
DND Do Not Disturb
Dose ambient sound level checking on Watch; /Applications/Dose.app
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, com.apple.ospredictiond
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, /System/Library/DuetExpertCenter; CoreDuet.framework, CoreKnowledge.framework, CorePrediction.framework, CascadeEngine.framework (link to Biome); launchd services: com.apple.coreduetd, com.apple.duetexpertd, com.apple.knowledge-agent, com.apple.ospredictiond
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
Ecosystem tracks usage of system functionalty by apps, can inform user to trigger responses; Ecosystem.framework; launchd services: com.apple.ecosystemd, com.apple.ecosystemagent
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
Energy Impact unitless metric for per-application energy consumption, machine-specific coefficients; /usr/share/pmenergy, 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
Exclave user-level portions of kernel or SEP services, used for paravirtualized access by VMs; /usr/libexec/init_exclavekit
Eye Relief screen distance warning for handheld devices; /Applications/EyeReliefUI.app
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
@@ -126,28 +136,31 @@ Family Circle Family Sharing; launchd services: com.apple.familycircled, com.app
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? 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
FiDES Fi? Distributed Evaluation Service? aggregates Differential Privacy data for unlinkability? used for emoji, Suggestions, Dictation; /System/Library/DistributedEvaluation; DistributedEvaluation.framework, FedStats.framework (private federated learning?)
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)
Find My location sharing by explicitly querying devices remotely or collateral beacon detection using Search Party; FMCore.framework, FMF.framework
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
Focus restriction modes for notification presentation; focus filters for in-app display restrictions, communicated 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 by GroupKit; 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
FSKit user space file system support; kernel stub file system is /System/Library/Extensions/lifs.kext; file systems are in /System/Library/ExtensionKit/Extensions/com.apple.fskit.*; launchd service: com.apple.filesystems.fskitd; extension point: com.apple.fskit.fsmodule
FUD Firmware Update Daemon; /var/db/fud; launchd service: com.apple.accessoryupdaterd
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
FRC Flow Residual Correction? optical-flow video analysis; FRC.framework
FSKit user space file system support; kernel stub file system is /System/Library/Extensions/lifs.kext; file systems are in /System/Library/ExtensionKit/Extensions/com.apple.fskit.*; launchd service: com.apple.filesystems.fskitd, com.apple.filesystems.doubleagentd (handling of Apple double files in user space); extension point: com.apple.fskit.fsmodule
FUD Firmware Update Daemon; see TSS, UARP; launchd service: com.apple.accessoryupdaterd
Game Mode auto-activates when games are shown full screen, throttles background work, lowers audio and input latency; launchd service: com.apple.gamepolicyd
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
Gizmo Apple Watch; watch settings managed by Companion iPhone; /Applications/Bridge.app, /System/Library/BridgeManifests
Greymatter Apple Intelligence; on-device language and diffusion models, larger server-based models in PCC; AFM refined for specific tasks (queries, summarization, categorization) by adapters (parameter for inserted network modules); grounded with context from Biome and intelligence stores; ~/Library/IntelligencePlatform; launchd service: com.apple.modelmanagerd (model residency management); /System/Library/ModelManager/Policy.plist; /Applications/Tamale.app (Camera Control integration); command line tool: csfdiagnose (cloud subscription features), modelmanagerdump
Group Activities SharePlay; sharing of media content and programmatic state over FaceTime calls; GroupActivities.framework, CopresenceCore.framework; launchd service: com.apple.telephonyutilities.callservicesd
GroupKit groups of IDS users with shared CloudKit (PCS) access; GroupKit.framework
GroupKit groups of IDS users with shared CloudKit (PCS) access; GroupKitCrypto.framework
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
HeadBoard derivative of SpringBoard for tvOS home screen; /Applications/HeadBoard.app, /Applications/PineBoard.app
Health Balance vitals app on Watch; /Applications/NanoHealthBalance.app
HLS HTTP Live Streaming
HomeEnergy HomeKit management for grid energy supply; EnergyKit.framework
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
Hyperion iCloud Photos, uses CloudKit; launchd service: com.apple.cloudphotod
@@ -157,28 +170,30 @@ iCDP iCloud Data Protection, codename for a set of enhancements to iCloud privac
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 Directory 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
IDS Identity Directory Service, also IDMS, Apple Account 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
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
Intent semantic interaction between app and system (or another app); used for Siri, Shortcuts, Maps (contextual suggestion), Widgets (configuration); definition by 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; SpeechRecognitionCore.framework; 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 Account; SpeechRecognitionCore.framework, ASRBridge.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
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
Journal diary app; JournalShared.framework
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 using SKP; 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.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 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
Liquid Glass UI design language, includes icon treatment; IconRendering.framework, LightSourceSupport.framework
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
@@ -186,40 +201,46 @@ LSM Latent Semantic Mapping, text analysis, used for spam filtering, command lin
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; used for Live Text and Visual Lookup; launchd service: com.apple.mediaanalysisd
Madrid iMessage; /System/Library/Messages
Madrid iMessage; /System/Library/Messages; BubbleKit.framework (message bubble UI)
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
MARRS Multimodal Reference Resolution; Marrs.framework
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
Mesa Touch ID; /Library/Catacomb
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
MLHost background machine learning service; launchd service: com.apple.mlhostd; /System/Library/MLHost; DeepThought.framework, LighthouseBackground.framework, LighthouseBitacoraFramework.framework,
Micro Location positioning service on macOS (because there is no GPS?); MicroLocation.framework; launchd service: com.apple.milod
MLHost background machine learning service; launchd service: com.apple.mlhostd; /System/Library/MLHost; DeepThought.framework, LighthouseBackground.framework, LighthouseBitacoraFramework.framework, Dendrite.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
MOC Managed Object Context; Core Data object space
Mondrian photo collage arrangement in Photos.app; Mondrian.framework
Mondrian photo collage arrangement in Photos.app; Mondrian.framework, GridZero.framework
MRT Malware Removal Tool; /Library/Apple/System/Library/CoreServices/MRT.app; superseded by XProtect
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
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
Nearby Interaction proximity-based interaction between devices; proximity measured using ultra wideband or derived from other technologies; used for Universal Control, tapping phones for AirDrop; NearbyInteraction.framework, Proximity.framework; launchd services: com.apple.aonsensed (always-on sense daemon), com.apple.nearbyd
Nebula sleep apnea detection on watchOS; BreathingAlgorithms.framework
New Device Outreach high-level Bluetooth device pairing flow; NewDeviceOutreach.framework, NDOAPI.framework, NDOUI.framework; launchd service: com.apple.ndoagent
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
NLU Natural Language Understanding; Greymatter Siri engine; SiriNLUTypes.framework, SiriNaturalLanguageParsing.framework
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, implements Private Relay; launchd service: com.apple.networkserviceproxy
OAH Rosetta; ahead-of-time compiler for Intel code on Apple Silicon, usable from Linux VMs by way of a custom binformat; /usr/libexec/rosetta
OAH Rosetta; ahead-of-time compiler for Intel code on Apple Silicon, usable from Linux VMs by way of a custom binformat; /usr/libexec/rosetta, /var/db/oah (AOT cache); launchd service: com.apple.oahd
ODR On-Demand Resources; loaded from App Store; launchd service: com.apple.appstored
Omni Search fuzzy semantic search with results recognized in images; OmniSearch.framework
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
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, populated from /System/Library/DirectoryServices/DefaultLocalDB; launchd service: com.apple.opendirectoryd; command line tools: dscacheutil, dscl, dsconfigad, dsconfigldap, dseditgroup, dsenableroot, dserr, dsexport, dsimport, dsmemberutil, odutil
OpenBSM Open Basic Security Module; deprecated security audit subsystem; /etc/security, /var/audit; launchd service: com.apple.auditd; command line tool: audit
Opus create slide shows from photos; Slideshows.framework
OSA Open Scripting Architecture; scripting of applications from different fontend languages (currently AppleScript and JavaScript); backed by Apple Events; command line tools: osacompile, osadecompile, osalang, osascript, sdef, sdp
@@ -227,47 +248,52 @@ OTUT One-Time Unlock Token; security mechanism to allow keybag unwrapping after
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)
Party Studio Karaoke mode on tvOS, where video from a paired phone is shown with effects; /System/Library/PrivateFrameworks/PartyStudio.*
Parsec Spotlight web results and searching of crowdsourced Intent deep links; server: *.smoot.apple.com; launchd services: com.apple.parsecd, com.apple.parsec-fbf (Feedback Flush to Differential Privacy); telemetry collection with Poirot: PoirotSQLite.framework, PoirotUDFs.framework, SearchOnDeviceAnalytics.framework
Party Studio Karaoke mode on tvOS, where video from a paired phone is shown with effects; PartyStudio.framework; /Applications/Sing.app
Passkey keypair used for authentication instead of password, synced via SOS, implements WebAuthn standard; keys can be used to login on separate device via QR code and Bluetooth proximity proof; AuthenticationServices.framework
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
PAT Private Access Tokens; blind challenge-response authentication; Apple server attests user validity to token issuer, issuer performs blind signature, websites receiving the token cannot identify user; used for Private Relay, can replace CAPTCHAs
PCC Private Cloud Compute; server-based AFM for AI, running on Apple Silicon managed by SEP; stateless computation, PAT to authorize user, Attestation of remote code by device, measurements published in Transparency; ~/Library/PrivateCloudCompute; launchd services: com.apple.privatecloudcomputed, com.apple.swtransparencyd
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, GroupKit, 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
Peak Power managing battery power draw; launchd service: com.apple.peakpowermanagerd; /System/Library/PPM/BatteryModels
PEC/PIR Private Encrypted Compute and Private Information Retrieval; used for parental controls for media and web; CipherML.framework; launchd service: com.apple.ciphermld
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
People contacts with Apple ID accounts within Group Activities and Shared With You
Pepper UI elements for Watch home screen and Chat, like Quickboard (canned replies), Animoji; PepperUICore.framework
People contacts with Apple Accounts within Group Activities and Shared With You
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
Plugin Extensions, XPC services bundled with apps or frameworks, discovery by Launch Services; extension points listed in /System/Library/ExtensionKit/ExtensionPoints; launchd service: com.apple.pluginkit.pkd; command line tool: pluginkit
PMC Performance Monitoring Counters; Recount.framework; /usr/share/kpep
PMP Port Mapping Protocol; Apple alternative to UPnP, Bonjour service: _acp-sync._tcp
Poster iPhone lock screen; PosterBoard.framework, PosterKit.framework; /Library/Wallpaper
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
Preview Shell skeleton for on-device UI previews during development; /System/Library/CoreServices/PreviewShell.app; PreviewShellKit.framework, XOJIT.framework (code live patching)
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 PAT
Proactive umbrella term for suggestions and completions based on Duet forecasting and User Activity context, also marketed as Siri features; PersonalizationPortrait.framework
Proactive umbrella term for suggestions, completions, and summarizations based on Duet forecasting, Biome, and Intent context; PersonalizationPortrait.framework, ProactiveMagicalMoments.framework, ProactiveSummarization.framework
Provenance per-file origin tracking, extended attribute com.apple.provenance stores ID into /var/db/SystemPolicyConfiguration/ExecPolicy
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
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, ProximityAppleIDSetup.framework; launchd service: com.apple.rapportd
RCS Rich Communication Services; messaging service in mobile networks, successor to SMS; IMRCSTransfer.framework; /System/Library/Messages/PlugIns/RCS.imservice
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), 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
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
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
Replicator notification sync from Companion iPhone, also drives remotely displayed live activities; ReplicatorServices.framework; launchd service: com.apple.replicatord
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
RTKit real-time runtime used for firmware of Apple Silicon co-processors; on top of CL4 in Apples cellular modem
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
Safety Monitor Check In; short-term location sharing in iMessage until a destination is reached; /Applications/SafetyMonitorApp.app
Salt & Pepper UI elements for Watch; SaltUICore.framework, PepperUICore.framework
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
@@ -276,17 +302,18 @@ 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; 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
SEP Secure Enclave Processor; dedicated ARM core for security services, runs CL4-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
Seymour Apple Fitness+; workout videos integrated with Watch sensors; SeymourCore.framework, Blackbeard.framework (personalisation and workout programs)
SF Symbols scalable UI symbols; rendered with various color treatments; SFSymbols.framework
Shared File List lists of recently opened files from apps that are stored with Launch Services; command line tool: sfltool; also manages login items and app-installed background daemons
Shared With You collaboration features between apps and iMessage; content shared via iMessage is surfaced in apps (Swift Transferable protocol), content in apps can be collaboratively edited and connected to an iMessage group; collaborations are expressed by keys derived from participant device keys, padded with a number of random keys to prevent tracking of device count, a merkle tree of those keys is used to prove inclusion of a specific device to an app; SharedWithYou.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: 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)
Sidecar using iPhone/iPad as Mac accessory: external camera and microphone (ContinuityCapture), camera for photos and scanning (DocumentCamera.framework), iPad as display over low-latency WiFi (llw interface) using avconferenced encoding; /Applications/Sidecar.app; 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
SIL Secure Indicator Light; microphone and camera indicator on iPads rendered in hardware
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
@@ -296,54 +323,61 @@ 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; 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
Sock Puppet Watch interaction that requires Companion iPhone
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
Splat Update Rapid Security Response, updates to Cryptex components without system restart
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
SPTM Secure Page Table Monitor; code in kernel-level GXF protects page table modifications; Trusted Execution Monitor (TXM) in user-level GXF implements policy and parts of AMFI
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 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
Stark CarPlay; iPhone provides video feeds for in-car displays; three layers composited by the car: remote UI (from iPhone), punch-through UI (back up camera), local UI (dashboard gauges: assets from iPhone, rendered by car, like Live Activities?), overlay UI (essential indicators); associate apps on iOS: /Applications/CarCamera.app, /Applications/Charge.app, /Applications/Climate.app, /Applications/Closures.app, /Applications/Media.app, /Applications/TirePressure.app, /Applications/Trip.app, /Applications/Vehicle.app
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; SEService.framework
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: 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 system-wide components formerly implemented as insecure plugins or kexts; current extension types: DriverKit, FSKit, Network, Endpoint Security, Core Media IO; /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
System Extension system-wide components formerly implemented as insecure plugins or kexts; current extension types: DriverKit, FSKit, Network, Endpoint Security, Core Media IO; /System/DriverKit, /System/Library/DriverExtensions, /Library/Preferences/com.apple.networkextension.plist; 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/SystemPolicyConfiguration; launchd service: com.apple.security.syspolicy (invoked by kernel through host special port 29); command line tool: spctl
Tailspin sampling of process stack traces; launchd service: com.apple.tailspind; command line tool: tailspin
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)
Tea component of Apples News, Stocks, and Weather apps, maybe interest personalization? TeaFoundation.framework, TeaDB.framework, TeaUI.framework
Template App code-less app-bundle, passed to an actual executable by LauncServices; created when adding websites in Safari to Dock/Springboard; run by /System/Volumes/Preboot/Cryptexes/App/System/Library/CoreServices/Web App.app
Time Machine automatic backup service, command line tools: tmdiagnose, tmutil
Tin Can Walkie Talkie on watchOS; /Applications/TinCan.app
Tones ringtones; ToneLibrary.framework
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, based on CONIKS, devices audit IDS records against transparency logs, log hashes gossiped over iMessage to detect split-view attacks; Transparency.framework; launchd service: com.apple.transparencyd; server: init-kt.apple.com
Transparency un-alterable append-only log to publish information; used for for ESS keys and PCC software hashes, based on CONIKS, devices audit IDS/PCC records against logs, root hashes gossiped over iMessage to detect split-view attacks; Transparency.framework; launchd service: com.apple.transparencyd; server: init-kt.apple.com
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
TTS Text To Speech, neural-network-based synthesis engine (Gryphon); command line tool: say; /System/Library/Speech
TVML TV Markup Language; declarative UI language for TV apps; TVMLKit.framework
UARP Universal Accessory Restore Protocol; CoreUARP.framework; launchd service: com.apple.uarppersonalizationd (personalized firmware)
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
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
Urchin Tides app on watchOS; /Applications/Urchin.app
USD Universal Scene Description; storage format for 3D assets; /usr/lib/usd; command line tools: usdcat, usdchecker, usdcrush, usdextract, usdrecord, usdtree, usdzip
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), Quick Note (context awareness); now part of Intents; 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
VA Video Acceleration; AppleVA.framework
VDAF Verifiable Distributed Aggregation Function; part of Differential Privacy; VDAF.framework
Viceroy video conferencing used by FaceTime and ReplayKit; ViceroyTrace.framework
Virtualisation running virtual machines on macOS; Hypervisor.framework (for basic VMs and vCPUs), Virtualization.framework (brings a robust set of device models)
VSDB volume status database; /var/db/volinfo.database; command line tool: vsdbutil
Waldo selects edge servers based on approximate location, part of Private Relay, seen in NSP
Wally private search in server-side database using homomorphic encryption; private information retrieval (PIR), private nearest neighbor search (PNNS); used for Caller ID, email logos, adult website filtering, points-of-interest lookup for photos
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 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; launchd service: com.apple.chronod (timeline management and sync)
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, ChronoServices.framework; extension point: com.apple.widgetkit-extension; launchd service: com.apple.chronod (timeline management and sync)
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
Window Manager implements Stage Manager; /System/Library/CoreServices/WindowManager.app
Window Manager implements Stage Manager; /System/Library/CoreServices/WindowManager.app; launchd service: com.apple.WindowManager.agent
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
XProtect signature-based malware scanner and remediation service; /Library/Apple/System/Library/CoreServices/XProtect.bundle
XProtect signature-based malware scanner and remediation service; /Library/Apple/System/Library/CoreServices/XProtect.bundle; command line tool: xprotect
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 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 Apple Advanced Typography; font format and rendering engine
7 Accounts launchd service: com.apple.accountsd; /System/Library/Accounts
8 ACDC Apple Chips in Data Centers; see PCC
9 ACDE Apple Connect Device External? ACDEClient.framework, old two-step verification, derived from a company-internal AppleConnect system?
10 ACFS Apple Clustered File System; deprecated file system for Xsan; acfs.framework
11 Acoustic ID Siri feature to recognize songs song recognition and matching with Apple catalog, playback on HomePod; /System/Library/Components/AudioDSP.component
12 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
13 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
14 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)
15 Aegir astronomy watch face and lock screen; /System/Library/CoreServices/AegirProxyApp.app
16 AFM Apple Foundation Model; pre-trained transformer and diffusion models for Greymatter, optimized for on-device use by quantization (with accuracy-recovery adapters) and palletization; command line tool: modelcatalogdump
17 AGC Apple Graphics Control, management of multiple displays and display port connections; launchd service: com.apple.displaypolicyd
18 AHAP Apple Haptic Audio Pattern; file format for simultaneous audio and haptic data; CoreHaptics.framework
19 AIR Apple Intermediate Representation; synthetic bytecode architecture target for GPU binary toolchain
20 ALF Application-Layer Firewall, launchd service: com.apple.alf (socketfilterfw) Application-Layer Firewall; implemented as a Network Extension (see System Extension); launchd service: com.apple.alf (socketfilterfw); command line tool: socketfilterfw
21 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
22 ALS Ambient Light Sensor, AmbientDisplay.framework
23 Amber Swift UI; SwiftUI.framework
24 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 Apple Mobile File Integrity, checks code integrity based on code signature, stronger enforcement with hardened runtime, validates entitlement restrictions and environment constraints (launch constraints, library constraints); 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
25 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
26 AMP Asynchronous Multiprocessing; performance and power-efficiency cores on Apple Silicon
27 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
32 AOS Apple Online Services? historical name for iCloud
33 Apache built-in web server; command line tool: apachectl
34 APFS Apple File System; copy-on-write file system with support for volume space-sharing, per-file encryption, and snapshots
35 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 Account login (DSID); credentials in apsd keychain; launchd service: com.apple.apsd; server: push.apple.com
36 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
37 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
38 AppleCare extended warranty; NewDeviceOutreach.framework; launchd service: com.apple.ndoagent
39 APT Adaptive Picture Timing? ProMotion; dynamic screen updates with 120Hz base frequency; AppleDisplayTCONControl.framework
40 Ask To parental-controlled user can ask parent for exceptions; launchd service: com.apple.asktod; AskToCore.framework parental-controlled user can ask parent for exceptions; launchd service: com.apple.asktod; AskTo.framework
41 ASL Apple System Logger, superseded by Unified Logging; /etc/asl; stored in /var/log/asl; launchd service: com.apple.syslogd; command line tool: syslog
42 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
43 Assertions power state management allowing applications to prevent sleeping; launchd service: com.apple.powerd; command line tools: caffeinate, pmset
44 Assessment checking of System Policy; term also used for AAC
45 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
46 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 Siri; speech recognition and semantic understanding, dialog management by CDM, Intent is communicated to and enacted on the client, uses TTS for speech output, Snippets to embed mini UIs into responses; /System/Library/Assistant, /System/Library/Snippets, AssistantServices.framework; server: *.siri.apple.com
47 ATS App Transport Security, sandbox mechanism only allowing TLS-secured connections
48 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
49 ATT App Tracking Transparency; apps declare user tracking on app store
50 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?
51 Authorization discretionary access control policies for high-level services; similar to PAM; policy stored in /var/db/auth.db
52 Avatar Memoji and Animoji, including pre-rendered iMessage stickers; AvatarKit.framework
53 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 tools: avbanalyse, avbdiagnose, avbutil
54 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.analyticsd
55 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
56 Background Assets assets that an app extension loads without the app being launched; BackgroundAssets.framework; extension point: com.apple.background-asset-downloader-extension; launchd service: com.apple.backgroundassets.user assets that an app extension loads without the app being launched; BackgroundAssets.framework; launchd service: com.apple.backgroundassets.user
57 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
58 Bifrost emergency satellite connectivity; /System/Library/LocationBundles/Bifrost.bundle
59 Biome CloudKit-synced real-time event streaming and processing; widely used, primarily Avatars/People? Siri?; BiomeStreams.framework, BiomeSync.framework; launchd services: com.apple.BiomeAgent, com.apple.biomesyncd CloudKit-synced streaming and storage of events like donated and invoked Intents; semantic index to ground AI with personal context; BiomeStreams.framework, BiomeSync.framework; launchd services: com.apple.BiomeAgent, com.apple.biomesyncd; embedding vector extraction and storage: ZeoliteFramework.framework
60 Blast Door sandboxed sanitization process for untrusted iMessage input; BlastDoor.framework sandboxed sanitization process for untrusted input, used for iMessage, IDS, Telephony, media analysis; BlastDoor.framework, CTBlastDoorSupport.framework, IDSBlastDoorSupport.framework, MediaAnalysisBlastDoorSupport.framework, MessagesBlastDoorSupport.framework, TelephonyBlastDoorSupport.framework
61 BOM Bill of Materials; format to store contents of installer Packages; command line tool: lsbom
62 Bonjour mDNS; launchd service: com.apple.mDNSResponder.reloaded; command line tool: dns-sd
63 Boot Cache disk cache pre-heating at boot time with typically loaded applications; /var/db/BootCaches; launchd service: com.apple.warmd
69 Cache Delete cleanup for various caches; /System/Library/CacheDelete; launchd service: com.apple.cache_delete (deleted)
70 CAML Core Animation Markup Language; XML file format for layers, shapes and animations
71 Carousel derivative of SpringBoard for Watch home screen, watch face, and notification center
72 CDM CBOR Continuous Dialog Manager; dialog with Siri; ContinuousDialogManagerService.framework, Marrs.framework; Concise Binary Object Representation; JSON-inspired compact binary data serialization; CBORLibrary.framework
73 Celestial CDHash media streaming used by ReplayKit for game broadcasts; Celestial.framework Code Directory Hash; a hash of hashes over the parts of a code bundle; command line tool: codesign
74 CDM Continuous Dialog Manager; natural dialog with Siri, MARRS for multi-modality; ContinuousDialogManagerService.framework
75 CEC Consumer Electronics Control; remote control for HDMI-connected devices; CoreRC.framework, IOCEC.framework
76 Celestial media streaming used by ReplayKit for in-app screen broadcasts; Celestial.framework; launchd service: com.apple.replayd
77 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
78 Chamois Stage Manager
79 CHIP Connected Home over IP; Matter; integrated into HomeKit; HomeKitMatter.framework Connected Home over IP; Matter; integrated into HomeKit, can use Thread as transport layer; HomeKitMatter.framework, CoreThread.framework; launchd services: com.apple.threadradiod, com.apple.ThreadCommissionerService
80 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: otctl (Octagon)
81 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
82 CL4 Apple’s variant of the L4 microkernel, derived from Pistachio/seL4 and Wombat/Darbat
83 Clarity customizable accessibility mode for simplified UI; ClarityFoundation.framework
84 Classroom school teachers can create assignments for student iPads and track progress in Schoolwork app; ClassKit.framework; launchd service: com.apple.studentd
85 Cloud Pairing part of Alloy, Bluetooth out-of-band pairing over iCloud for Continuity; launchd service: com.apple.BTServer.cloudpairing (cloudpaird)
86 CMAS Commerial Mobile Alert System, now known as Wireless Emergency Alerts (WEA)
87 Commpage user-mapped kernel data, like vdso/vsyscall on Linux; mapped at 0x7fffffe00000
88 Communications Filter recipient blocking for iMessage, FaceTime, Mail; launchd service: com.apple.cmfsyncagent
89 Companion iPhone that is paired with Watch; communication uses Alloy over IPsec over Bluetooth iPhone that is linked with Watch, Mac, or Apple TV; communication with Watch uses Alloy over IPsec over Bluetooth, AWDL on demand; launchd service: com.apple.companiond; Bonjour service: _companion-link._tcp
90 Contact Key Verification code for manual verification of iMessage keys; code identifies a long-lived account key stored in iCloud Keychain, which signs all ESS device keys
91 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, iPhone Mirroring, SMS relay, Universal Clipboard, Watch unlock, WiFi call relay and others; SMS relay works by proxying to iMessage, other services use Alloy for signalling and AWDL for payload; /System/Applications/iPhone Mirroring.app, ScreenContinuityServices.framework
92 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
93 CPML CorePrediction Machine Learning; CPMLBestShim.framework
94 CRD Conference Room Display; Apple TV mode
95 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) Cryptographically sealed Extension of SSV, mount-invisible overlay of the root volume, allows lightweight updates as part of Rapid Security Response; /System/Cryptexes (mountpoint), /System/Volumes/Preboot/*/cryptex1/current/*.dmg (disk images)
96 CSR Configurable Security Restrictions; XNU subsystem that is the basis for SIP
97 CTK Crypto Token Kit; smart card management, also for the Secure Element on iOS? launchd service: com.apple.ctkd; command line tool: sc_auth
98 CTS Centralized Task Scheduling; execution of DAS tasks; /System/Library/UserEventPlugins/com.apple.cts.plugin
100 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
101 Daily Briefing Siri giving an overview of information for the day; SiriDailyBriefingInternal.framework
102 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)
103 Darwin Directory static store for users and groups, saves Open Directory interaction for the local case? /usr/lib/system/libsystem_darwindirectory.dylib, /System/Library/DarwinDirectory, /private/var/db/DarwinDirectory; command line tool: dddiagnose
104 DAS Duet Activity Scheduler; scheduling policy engine behind NSBackgroundActivityScheduler and XPC activities; /System/Library/DuetActivityScheduler; launchd service: com.apple.dasd
105 Data Detectors text analysis to highlight phone numbers, street addresses, and the like; DataDetectors.framework
106 Data Vault directories with the UF_DATAVAULT special flag; CSR limits access to one application
113 DFU Device Firmware Update; special boot mode where iOS has not booted and the system can be installed over the Lightning connection
114 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
115 Digital Separation safety check feature to inhibit sharing relationships; DigitalSeparation.framework
116 DMC Device Management Client; part of MDM; DMCUtilities.framework Device Management Client; part of MDM; DMCApps.framework, DMCUtilities.framework
117 DMC Disk Mount Conditioner; simulates slow IO devices; command line tool: dmc
118 DND Do Not Disturb
119 Dose ambient sound level checking on Watch; /Applications/Dose.app
120 DSID Destination Signaling Identifier, unique ID for IDS login on a specific device
121 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
122 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, com.apple.ospredictiond 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, /System/Library/DuetExpertCenter; CoreDuet.framework, CoreKnowledge.framework, CorePrediction.framework, CascadeEngine.framework (link to Biome); launchd services: com.apple.coreduetd, com.apple.duetexpertd, com.apple.knowledge-agent, com.apple.ospredictiond
123 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
124 EAS Exchange Active Sync; network protocol for accessing Microsoft Exchange servers
125 Ecosystem tracks usage of system functionalty by apps, can inform user to trigger responses; Ecosystem.framework; launchd services: com.apple.ecosystemd, com.apple.ecosystemagent
126 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
127 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, launchd services: com.apple.sysmond, com.apple.thermald; command line tool: powermetrics
128 Engram Messages in iCloud; devices store received iMessages in CloudKit; Engram.framework
129 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
130 ESS IDS user directory, public key distribution for iMessage and CloudKit sharing, uses Transparency; server: *.ess.apple.com; launchd service: com.apple.identityservicesd
131 Exclave user-level portions of kernel or SEP services, used for paravirtualized access by VMs; /usr/libexec/init_exclavekit
132 Eye Relief screen distance warning for handheld devices; /Applications/EyeReliefUI.app
133 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)
134 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
136 FDE Full Disk Encryption, FileVault; command line tool: fdesetup, sysadminctl
137 FDR Factory Data/Device Reset? ensures that no downgrades are performed? servers: skl.apple.com, gg.apple.com; /System/Library/FDR
138 Feldspar Apple News; Silex.framework
139 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 Fi? Distributed Evaluation Service? aggregates Differential Privacy data for unlinkability? used for emoji, Suggestions, Dictation; /System/Library/DistributedEvaluation; DistributedEvaluation.framework, FedStats.framework (private federated learning?)
140 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
141 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) location sharing by explicitly querying devices remotely or collateral beacon detection using Search Party; FMCore.framework, FMF.framework
142 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
143 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 restriction modes for notification presentation; focus filters for in-app display restrictions, communicated by Intents; Focus.framework, DoNotDisturb.framework; local settings in ~/Library/DoNotDisturb
144 FollowUp user interaction for Secure Backup wrapping with device passcode, CoreFollowUp.framework; launchd service: com.apple.followupd
145 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 by GroupKit; 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
146 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 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
147 FSKit FRC user space file system support; kernel stub file system is /System/Library/Extensions/lifs.kext; file systems are in /System/Library/ExtensionKit/Extensions/com.apple.fskit.*; launchd service: com.apple.filesystems.fskitd; extension point: com.apple.fskit.fsmodule Flow Residual Correction? optical-flow video analysis; FRC.framework
148 FUD FSKit Firmware Update Daemon; /var/db/fud; launchd service: com.apple.accessoryupdaterd user space file system support; kernel stub file system is /System/Library/Extensions/lifs.kext; file systems are in /System/Library/ExtensionKit/Extensions/com.apple.fskit.*; launchd service: com.apple.filesystems.fskitd, com.apple.filesystems.doubleagentd (handling of Apple double files in user space); extension point: com.apple.fskit.fsmodule
149 FUD Firmware Update Daemon; see TSS, UARP; launchd service: com.apple.accessoryupdaterd
150 Game Mode auto-activates when games are shown full screen, throttles background work, lowers audio and input latency; launchd service: com.apple.gamepolicyd
151 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
152 Gizmo Apple Watch; watch settings managed by Companion; /Applications/Bridge.app, /System/Library/BridgeManifests Apple Watch; watch settings managed by Companion iPhone; /Applications/Bridge.app, /System/Library/BridgeManifests
153 Greymatter Apple Intelligence; on-device language and diffusion models, larger server-based models in PCC; AFM refined for specific tasks (queries, summarization, categorization) by adapters (parameter for inserted network modules); grounded with context from Biome and intelligence stores; ~/Library/IntelligencePlatform; launchd service: com.apple.modelmanagerd (model residency management); /System/Library/ModelManager/Policy.plist; /Applications/Tamale.app (Camera Control integration); command line tool: csfdiagnose (cloud subscription features), modelmanagerdump
154 Group Activities SharePlay; sharing of media content and programmatic state over FaceTime calls; GroupActivities.framework, CopresenceCore.framework; launchd service: com.apple.telephonyutilities.callservicesd
155 GroupKit groups of IDS users with shared CloudKit (PCS) access; GroupKit.framework groups of IDS users with shared CloudKit (PCS) access; GroupKitCrypto.framework
156 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
157 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
158 HAP Home Automation Protocol; CoreHAP.framework
HDA High Definition Audio; HDAInterface.framework
159 HDI Hard Disk Image; command line tool: hdiutil
160 HeadBoard derivative of SpringBoard for tvOS home screen; /Applications/HeadBoard.app, /Applications/PineBoard.app
161 Health Balance vitals app on Watch; /Applications/NanoHealthBalance.app
162 HLS HTTP Live Streaming
163 HomeEnergy HomeKit management for grid energy supply; EnergyKit.framework
164 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
165 HSM Hardware Security Module; HSM fleet runs escrow service for Secure Backup
166 Hyperion iCloud Photos, uses CloudKit; launchd service: com.apple.cloudphotod
170 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
171 iCSC iCloud Security Code, credential wrapping for Secure Backup, previously used a separate code, with HSA2/iCDP uses device passcodes
172 IDAM Inter-Device Audio and MIDI; audio connection between devices
173 IDS Identity Directory 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 Directory Service, also IDMS, Apple Account 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
174 IDV Identity Verification? Touch ID and Face ID; /System/Library/AccessibilityBundles/CoreIDVUI.axbundle
175 IM Instant Messaging; usually means iMessage and FaceTime
176 IMG4 boot files (Mach-O binaries or configuration data) with ASN.1 signature, contains RemotePolicy certificate constraints to restrict Boot Policy evaluation
177 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 semantic interaction between app and system (or another app); used for Siri, Shortcuts, Maps (contextual suggestion), Widgets (configuration); definition by 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
178 IOKit device driver subsystem for in-kernel and DriverKit drivers, command line tool: ioreg
179 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 dictation, customized on server with selected user data (contacts, app names, music titles, HomeKit names, Siri Shortcut phrases), not tied to Apple Account; SpeechRecognitionCore.framework, ASRBridge.framework; server: guzzoni.apple.com
180 ISP Image Signal Processor; camera imaging circuit in iPhones
181 ITML iTunes Markup Language; metdata tagging for media services; ITMLKit.framework
182 ITP Intelligent Tracking Prevention, cross-site tracking defenses in Safari, statistics and user interaction classify sites, cookies are partitioned and access is restricted
183 JARVIS Just A Rather Very Intelligent Scheduler, Mesos cluster manager for Siri, iCloud, AMS
184 Jellyfish Animoji; /Applications/Jellyfish.app
185 Jetsam reclaiming of purgeable memory and termination of apps during memory pressure
186 Journal diary app; JournalShared.framework
187 JSC JavaScript Core; JavaScriptCore.framework; command line tool: jsc
188 Kalamata codename for the transition from x86 to ARM-based Apple Silicon
189 Kerberos single-sign-on mechanism; Heimdal.framework; command line tools: kinit, ktutil
190 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)
191 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
192 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 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.secd
193 Keychain storage for credentials; launchd service: com.apple.securityd; command line tools: certtool, security, systemkeychain
194 KIP Kernel Integrity Protection, locking of physical memory pages to prevent changes to kernel
195 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
196 Liquid Glass UI design language, includes icon treatment; IconRendering.framework, LightSourceSupport.framework
197 Live Files user mode filesystems, currently FAT, ExFAT, NTFS on external storage; UserFS.framework, UVFSXPCService.framework; launchd service: com.apple.filesystems.userfsd
198 Liverpool PCS codename for CloudKit
199 LKDC Local Key Distribution Center, Kerberos on client machines
201 Mac Buddy historic name for Setup Assistant
202 MAC Policy Mandatory Access Control subsystem in XNU, based on TrustedBSD, implements policy hooks for restricted kernel operations; current policies: AMFI, Seatbelt, Quarantine, CSR
203 Machine Learning Vision.framework, Espresso.framework, Futhark.framework, PhotoAnalysis.framework; used for Live Text and Visual Lookup; launchd service: com.apple.mediaanalysisd
204 Madrid iMessage; /System/Library/Messages iMessage; /System/Library/Messages; BubbleKit.framework (message bubble UI)
205 Manatee PCS key for some CloudKit containers are synced via CKKS, so data is unreadable to Apple (credential management codenames: Plesio, Stingray, Cuttlefish)
206 Mandrake emergency siren on Apple Watch Ultra; /Applications/Mandrake.app
207 Mangrove transfering UI tiles over XPC; Mangrove.framework, IOSurface.framework
208 Marco Marco.framework, something about IDS and communication (iMessage, Calls), logging?
209 Marklar codename from the PowerPC era for the port to x86, served the transition to Intel CPUs
210 MARRS Multimodal Reference Resolution; Marrs.framework
211 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
212 MCX Managed Client for OS X, preference management for settings from configuration profiles, /Library/Managed Preferences, command line tools: mcxquery, mcxrefresh
213 MDM Mobile Device Management; server software to manage fleets of iOS and macOS devices; uses configuration profiles to manage preferences; ConfigurationProfiles.framework
214 MDS Module Directory Services, ancient part of the old security APIs (CSDA, CSSM)
215 Memory Debugging uses Taskport; command line tools: heap, leaks, malloc_history, stringdups, vmmap
216 Mesa Touch ID; /Library/Catacomb; /var/db/bkad.db Touch ID; /Library/Catacomb
217 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
218 MLHost Micro Location background machine learning service; launchd service: com.apple.mlhostd; /System/Library/MLHost; DeepThought.framework, LighthouseBackground.framework, LighthouseBitacoraFramework.framework, positioning service on macOS (because there is no GPS?); MicroLocation.framework; launchd service: com.apple.milod
219 MLHost background machine learning service; launchd service: com.apple.mlhostd; /System/Library/MLHost; DeepThought.framework, LighthouseBackground.framework, LighthouseBitacoraFramework.framework, Dendrite.framework
220 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
221 Mobile prefix for iOS
222 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
223 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
224 MOC Managed Object Context; Core Data object space
225 Mondrian photo collage arrangement in Photos.app; Mondrian.framework photo collage arrangement in Photos.app; Mondrian.framework, GridZero.framework
226 MRT Malware Removal Tool; /Library/Apple/System/Library/CoreServices/MRT.app; superseded by XProtect
227 Multipeer Connectivity ad-hoc networking; Bonjour for discovery; WiFi, AWDL, Bluetooth, or Ethernet as transport; optional encryption and certificate-based authentication; MultipeerConnectivity.framework
228 Nano prefix for watchOS
229 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 proximity-based interaction between devices; proximity measured using ultra wideband or derived from other technologies; used for Universal Control, tapping phones for AirDrop; NearbyInteraction.framework, Proximity.framework; launchd services: com.apple.aonsensed (always-on sense daemon), com.apple.nearbyd
230 Nebula sleep apnea detection on watchOS; BreathingAlgorithms.framework
231 New Device Outreach high-level Bluetooth device pairing flow; NewDeviceOutreach.framework, NDOAPI.framework, NDOUI.framework; launchd service: com.apple.ndoagent
232 Newton fall detection on watchOS
233 NLP Natural Language Processing; NLP.framework; related to mecabra libraries, a linguistic engine for Chinese and Japanese; /usr/share/mecabra, /usr/share/tokenizer
234 NLU Natural Language Understanding; Greymatter Siri engine; SiriNLUTypes.framework, SiriNaturalLanguageParsing.framework
235 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
236 Noticeboard User Notifications for Software Update and App Store, Noticeboard.framework; launchd services: com.apple.noticeboard.state (nbstated), com.apple.noticeboard.agent (nbagent)
237 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
238 NSP Network Service Proxy; per-app VPN and proxy settings, implements Private Relay; launchd service: com.apple.networkserviceproxy
239 OAH Rosetta; ahead-of-time compiler for Intel code on Apple Silicon, usable from Linux VMs by way of a custom binformat; /usr/libexec/rosetta Rosetta; ahead-of-time compiler for Intel code on Apple Silicon, usable from Linux VMs by way of a custom binformat; /usr/libexec/rosetta, /var/db/oah (AOT cache); launchd service: com.apple.oahd
240 ODR On-Demand Resources; loaded from App Store; launchd service: com.apple.appstored
241 Omni Search fuzzy semantic search with results recognized in images; OmniSearch.framework
242 Onboarding data protection splash screen shown by service-connected apps; /System/Library/OnBoardingBundles; OnBoardingKit.framework
243 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, populated from /System/Library/DirectoryServices/DefaultLocalDB; launchd service: com.apple.opendirectoryd; command line tools: dscacheutil, dscl, dsconfigad, dsconfigldap, dseditgroup, dsenableroot, dserr, dsexport, dsimport, dsmemberutil, odutil
244 OpenBSM Open Basic Security Module; deprecated security audit subsystem; /etc/security, /var/audit; launchd service: com.apple.auditd; command line tool: audit
245 Opus create slide shows from photos; Slideshows.framework
246 OSA Open Scripting Architecture; scripting of applications from different fontend languages (currently AppleScript and JavaScript); backed by Apple Events; command line tools: osacompile, osadecompile, osalang, osascript, sdef, sdp
248 PAC Pointer Authentication Codes; pointers signed in unused bits to prevent ROP attacks
249 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)
250 Packet Filter network traffic filtering subsystem from OpenBSD; command line tool: pfctl
251 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 Intent deep links; server: *.smoot.apple.com; launchd services: com.apple.parsecd, com.apple.parsec-fbf (Feedback Flush to Differential Privacy); telemetry collection with Poirot: PoirotSQLite.framework, PoirotUDFs.framework, SearchOnDeviceAnalytics.framework
252 Party Studio Karaoke mode on tvOS, where video from a paired phone is shown with effects; /System/Library/PrivateFrameworks/PartyStudio.* Karaoke mode on tvOS, where video from a paired phone is shown with effects; PartyStudio.framework; /Applications/Sing.app
253 Passkey keypair used for authentication instead of password, synced via SOS, implements WebAuthn standard; keys can be used to login on separate device via QR code and Bluetooth proximity proof; AuthenticationServices.framework
254 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
255 Pasteboard storage for cut, copy, and paste; type of content remembered as UTI; launchd service: com.apple.pboard; command line tools: pbcopy, pbpaste
256 PAT Private Access Tokens; blind challenge-response authentication; Apple server attests user validity to token issuer, issuer performs blind signature, websites receiving the token cannot identify user; used for Private Relay, can replace CAPTCHAs
257 PCC Private Cloud Compute; server-based AFM for AI, running on Apple Silicon managed by SEP; stateless computation, PAT to authorize user, Attestation of remote code by device, measurements published in Transparency; ~/Library/PrivateCloudCompute; launchd services: com.apple.privatecloudcomputed, com.apple.swtransparencyd
258 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, GroupKit, Manatee; ProtectedCloudStorage.framework; /System/Library/Preferences/ProtectedCloudStorage; command line tool: pcsstatus
259 PCSC Personal Computer Smart Card; PCSC.framework, uses CTK
260 PDE Print Dialog Extension; old name, not a proper Extension
261 Peak Power managing battery power draw; launchd service: com.apple.peakpowermanagerd; /System/Library/PPM/BatteryModels
262 PEC/PIR Private Encrypted Compute and Private Information Retrieval; used for parental controls for media and web; CipherML.framework; launchd service: com.apple.ciphermld
263 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
264 People contacts with Apple ID accounts within Group Activities and Shared With You contacts with Apple Accounts within Group Activities and Shared With You
Pepper UI elements for Watch home screen and Chat, like Quickboard (canned replies), Animoji; PepperUICore.framework
265 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
266 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
267 Piano Mover Mail Drop; bulk mail attachments transfered over PCS; not to be confused with storage for iMessage attachments, which uses a CloudKit container
268 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; extension points listed in /System/Library/ExtensionKit/ExtensionPoints; launchd service: com.apple.pluginkit.pkd; command line tool: pluginkit
269 PMC Performance Monitoring Counters; Recount.framework; /usr/share/kpep
270 PMP Port Mapping Protocol; Apple alternative to UPnP, Bonjour service: _acp-sync._tcp
271 Poster iPhone lock screen; PosterBoard.framework, PosterKit.framework; /Library/Wallpaper
272 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
273 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
274 Preview Shell skeleton for on-device UI previews during development; /System/Library/CoreServices/PreviewShell.app; PreviewShellKit.framework, XOJIT.framework (code live patching)
275 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 PAT
276 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, completions, and summarizations based on Duet forecasting, Biome, and Intent context; PersonalizationPortrait.framework, ProactiveMagicalMoments.framework, ProactiveSummarization.framework
277 Provenance per-file origin tracking, extended attribute com.apple.provenance stores ID into /var/db/SystemPolicyConfiguration/ExecPolicy
278 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?
279 Quagga framework for QR and barcode decoding; Quagga.framework
280 Quick Action extension type for quick interaction with foreign content within a host app; extension points: com.apple.services, com.apple.ui-services
281 Quick Look file preview and thumbnail generation; comand line tool: qlmanage
282 RAOP Remote Audio Output Protocol, AirPlay; Bonjour service: _raop._tcp
283 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, ProximityAppleIDSetup.framework; launchd service: com.apple.rapportd
284 RCS Rich Communication Services; messaging service in mobile networks, successor to SMS; IMRCSTransfer.framework; /System/Library/Messages/PlugIns/RCS.imservice
285 Recents recently used items (not files) in various applications, synced with Synced Defaults; CoreRecents.framework, /System/Library/Recents; launchd service: com.apple.recentsd
286 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 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
287 Remote Pairing Mobile Device pairing without wired connection; RemotePairingDevice.framework; Bonjour services: _remotepairing._tcp, _remotepairing-manual-pairing._tcp
288 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
289 Replicator notification sync from Companion iPhone, also drives remotely displayed live activities; ReplicatorServices.framework; launchd service: com.apple.replicatord
290 Revisions document autosave and auto-versioning; stored in .DocumentRevisions-V100; GenerationalStorage.framework; launchd service: com.apple.revisiond
291 Routine frequently visited locations on iOS, interacts with Duet; launchd service: com.apple.routined
292 RTC Real-time Telemetry and Crash reporting; RTCReporting.framework; launchd service: com.apple.rtcreportingd
293 RTKit operating system used on Apple Silicon for firmware of co-processors real-time runtime used for firmware of Apple Silicon co-processors; on top of CL4 in Apple’s cellular modem
294 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
295 Safety Monitor Check In; short-term location sharing in iMessage until a destination is reached; /Applications/SafetyMonitorApp.app
296 Salt & Pepper UI elements for Watch; SaltUICore.framework, PepperUICore.framework
297 SBPL Sandbox Profile Language; a TinyScheme-based embedded DSL for Seatbelt profiles
298 SCIP System Coprocessor Integrity Protection; like KIP, but for SEP, ISP, Motion coprocessor
299 Screen Reader VoiceOver and Braille; /System/Library/ScreenReader; ScreenReader.framework
302 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
303 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)
304 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
305 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 Secure Enclave Processor; dedicated ARM core for security services, runs CL4-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
306 Sequoia translation; downloadable language models can run on-device; /Applications/SequoiaTranslator.app, Translation.framework
307 Seymour Apple Fitness+; workout videos integrated with Watch sensors; SeymourCore.framework Apple Fitness+; workout videos integrated with Watch sensors; SeymourCore.framework, Blackbeard.framework (personalisation and workout programs)
308 SF Symbols scalable UI symbols; rendered with various color treatments; SFSymbols.framework
309 Shared File List lists of recently opened files from apps that are stored with Launch Services; command line tool: sfltool; also manages login items and app-installed background daemons
310 Shared With You collaboration features between apps and iMessage; content shared via iMessage is surfaced in apps (Swift Transferable protocol), content in apps can be collaboratively edited and connected to an iMessage group; collaborations are expressed by keys derived from participant device keys, padded with a number of random keys to prevent tracking of device count, a merkle tree of those keys is used to prove inclusion of a specific device to an app; SharedWithYou.framework
311 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
312 Shazam audio (especially music) recognition service; ShazamKit.framework; launchd service: com.apple.shazamd; command line tool: shazam
313 Shoebox Passbook
314 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) using iPhone/iPad as Mac accessory: external camera and microphone (ContinuityCapture), camera for photos and scanning (DocumentCamera.framework), iPad as display over low-latency WiFi (llw interface) using avconferenced encoding; /Applications/Sidecar.app; SidecarCore.framework; launchd services: com.apple.sidecar-display-agent (SidecarDisplayAgent), com.apple.sidecar-relay (SidecarRelay)
315 Signpost telemetry API to report points of interest in code; launchd service: com.apple.signpost.signpost_reporter
316 SIL Secure Indicator Light; microphone and camera indicator on iPads rendered in hardware
317 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
318 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
319 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
323 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
324 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
325 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
326 Sock Puppet Watch interaction that requires Companion device Watch interaction that requires Companion iPhone
327 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
328 SPI System Private Interface; /System/Library/PrivateFrameworks
329 Splat Update Rapid Security Response, updates to Cryptex components without system restart
330 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)
331 SPRR Shadow Permission Remap Register? feature of Apple Silicon to dynamically reintepret page permissions
332 SPTM Secure Page Table Monitor; code in kernel-level GXF protects page table modifications; Trusted Execution Monitor (TXM) in user-level GXF implements policy and parts of AMFI
333 SRP Secure Remote Password; standard cryptographic protocol for proving knowledge of a secret such that attackers cannot brute-force the secret; AppleSRP.framework
334 SSO Single Sign-On
335 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
336 Stark CarPlay CarPlay; iPhone provides video feeds for in-car displays; three layers composited by the car: remote UI (from iPhone), punch-through UI (back up camera), local UI (dashboard gauges: assets from iPhone, rendered by car, like Live Activities?), overlay UI (essential indicators); associate apps on iOS: /Applications/CarCamera.app, /Applications/Charge.app, /Applications/Climate.app, /Applications/Closures.app, /Applications/Media.app, /Applications/TirePressure.app, /Applications/Trip.app, /Applications/Vehicle.app
337 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 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; SEService.framework
338 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
339 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
340 Symbols debug symbols for backtraces; CoreSymbolication.framework; launchd services: com.apple.coresymbolicationd; command line tools: atos, symbols, symbolscache
341 Symptoms network diagnostics; Symptoms.framework; /var/networkd/db/netusage.sqlite; launchd service: com.apple.symptomsd (invoked by kernel through host special port 27)
342 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
343 System Configuration SystemConfiguration.framework; launchd service: com.apple.configd; command line tool: scutil
344 System Extension system-wide components formerly implemented as insecure plugins or kexts; current extension types: DriverKit, FSKit, Network, Endpoint Security, Core Media IO; /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-wide components formerly implemented as insecure plugins or kexts; current extension types: DriverKit, FSKit, Network, Endpoint Security, Core Media IO; /System/DriverKit, /System/Library/DriverExtensions, /Library/Preferences/com.apple.networkextension.plist; command line tool: systemextensionsctl; launchd services: com.apple.sysextd, com.apple.nesessionmanager, com.apple.endpointsecurity.endpointsecurityd; command line tool: eslogger
345 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 Gatekeeper; policy engine for application launches and kext loading, malware signatures from /Library/Apple/System/Library/CoreServices/XProtect.bundle; /var/db/SystemPolicyConfiguration; launchd service: com.apple.security.syspolicy (invoked by kernel through host special port 29); command line tool: spctl
346 Tailspin sampling of process stack traces; launchd service: com.apple.tailspind; command line tool: tailspin
347 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
348 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
349 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)
350 Tea component of Apple’s News, Stocks, and Weather apps, maybe interest personalization? TeaFoundation.framework, TeaDB.framework, TeaUI.framework
351 Template App code-less app-bundle, passed to an actual executable by LauncServices; created when adding websites in Safari to Dock/Springboard; run by /System/Volumes/Preboot/Cryptexes/App/System/Library/CoreServices/Web App.app
352 Time Machine automatic backup service, command line tools: tmdiagnose, tmutil
353 Tin Can Walkie Talkie on watchOS; /Applications/TinCan.app
354 Tones ringtones; ToneLibrary.framework
355 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)
356 Transparency key transparency for ESS keys, based on CONIKS, devices audit IDS records against transparency logs, log hashes gossiped over iMessage to detect split-view attacks; Transparency.framework; launchd service: com.apple.transparencyd; server: init-kt.apple.com un-alterable append-only log to publish information; used for for ESS keys and PCC software hashes, based on CONIKS, devices audit IDS/PCC records against logs, root hashes gossiped over iMessage to detect split-view attacks; Transparency.framework; launchd service: com.apple.transparencyd; server: init-kt.apple.com
357 TSS Tatsu Signing Server; online verification for firmware signatures; server: gs.apple.com
358 TTS Text To Speech, neural-network-based synthesis engine (Gryphon); command line tool: say; /System/Library/Speech, /System/Library/TTSPlugins Text To Speech, neural-network-based synthesis engine (Gryphon); command line tool: say; /System/Library/Speech
359 TVML TV Markup Language; declarative UI language for TV apps; TVMLKit.framework
360 UARP Universal Accessory Restore Protocol; CoreUARP.framework; launchd service: com.apple.uarppersonalizationd (personalized firmware)
361 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)
362 UID unique ID key, used as root key for cryptographic subsystems, generated during manufacturing by SEP and fused into hardware, only accessible by SEP
363 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
364 USD Urchin Universal Scene Description; storage format for 3D assets; /usr/lib/usd Tides app on watchOS; /Applications/Urchin.app
365 User Activity USD 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 Universal Scene Description; storage format for 3D assets; /usr/lib/usd; command line tools: usdcat, usdchecker, usdcrush, usdextract, usdrecord, usdtree, usdzip
366 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), Quick Note (context awareness); now part of Intents; UserActivity.framework; launchd service: com.apple.coreservices.useractivityd
367 User Notifications user interface for notification center; launchd service: com.apple.usernoted
368 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
369 VA Video Acceleration; AppleGVA.framework, AppleVA.framework, AppleVPA.framework Video Acceleration; AppleVA.framework
370 VDAF Verifiable Distributed Aggregation Function; part of Differential Privacy; VDAF.framework
371 Viceroy video conferencing used by FaceTime and ReplayKit; ViceroyTrace.framework
372 Virtualisation running virtual machines on macOS; Hypervisor.framework (for basic VMs and vCPUs), Virtualization.framework (brings a robust set of device models)
373 VSDB volume status database; /var/db/volinfo.database; command line tool: vsdbutil
374 Waldo selects edge servers based on approximate location, part of Private Relay, seen in NSP
375 Wally private search in server-side database using homomorphic encryption; private information retrieval (PIR), private nearest neighbor search (PNNS); used for Caller ID, email logos, adult website filtering, points-of-interest lookup for photos
376 WFS WebDAV File Sharing; built-in file sharing with Apache; /etc/wfs; command line tool: wfsctl
377 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; launchd service: com.apple.chronod (timeline management and sync) 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, ChronoServices.framework; extension point: com.apple.widgetkit-extension; launchd service: com.apple.chronod (timeline management and sync)
378 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
379 Window Manager implements Stage Manager; /System/Library/CoreServices/WindowManager.app implements Stage Manager; /System/Library/CoreServices/WindowManager.app; launchd service: com.apple.WindowManager.agent
380 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
381 xART eXtended Anti-Replay Technology; persistent storage for SEP, used by Mesa; /System/Volumes/xarts; launchd service: com.apple.xartstorageremoted; command line tool: xartutil
382 XCS Xcode Server; continuous integration server; command line tools: xcscontrol, xcsdiagnose
383 XProtect signature-based malware scanner and remediation service; /Library/Apple/System/Library/CoreServices/XProtect.bundle signature-based malware scanner and remediation service; /Library/Apple/System/Library/CoreServices/XProtect.bundle; command line tool: xprotect