Adding client_server CFMessagePort example

X. NU/custom/mach_ipc/client_server_CFMessagePort/Makefile

@@ -0,0 +1,15 @@
+CC = clang
+FRAMEWORK = -framework Foundation
+
+all: client server
+
+client: client.m
+	$(CC) $(FRAMEWORK) client.m -o client
+
+server: server.m
+	$(CC) $(FRAMEWORK) server.m -o server
+
+clean:
+	rm -f client server *.o
+
+.PHONY: all clean

X. NU/custom/mach_ipc/client_server_CFMessagePort/client.m

@@ -0,0 +1,16 @@
+#import <Foundation/Foundation.h>
+
+int main(int argc, char *argv[]) {
+    @autoreleasepool {
+        if (argc != 2) return 1;
+        
+        CFMessagePortRef port = CFMessagePortCreateRemote(NULL, CFSTR("com.crimson.message_service"));
+        if (port) {
+            NSString *msg = [NSString stringWithUTF8String:argv[1]];
+            NSData *data = [msg dataUsingEncoding:NSUTF8StringEncoding];
+            CFMessagePortSendRequest(port, 0, (__bridge CFDataRef)data, 1, 1, NULL, NULL);
+            CFRelease(port);
+        }
+    }
+    return 0;
+}

X. NU/custom/mach_ipc/client_server_CFMessagePort/server.m

@@ -0,0 +1,18 @@
+// server.m
+// clang -framework Foundation server.m -o server
+#import <Foundation/Foundation.h>
+
+static CFDataRef callback(CFMessagePortRef port, SInt32 msgid, CFDataRef data, void *info) {
+    NSLog(@"Received: %@", [[NSString alloc] initWithData:(__bridge NSData *)data encoding:NSUTF8StringEncoding]);
+    return NULL;
+}
+
+int main() {
+    @autoreleasepool {
+        CFMessagePortRef port = CFMessagePortCreateLocal(NULL, CFSTR("com.crimson.message_service"), callback, NULL, NULL);
+        CFRunLoopSourceRef source = CFMessagePortCreateRunLoopSource(NULL, port, 0);
+        CFRunLoopAddSource(CFRunLoopGetCurrent(), source, kCFRunLoopCommonModes);
+        [[NSRunLoop currentRunLoop] run];
+    }
+    return 0;
+}