KnowingIfAppWasLaunchedFromLoginItems

To know if your application was launched because it is a login item, as opposed to being launched explicitly by the user from the Finder, use the code below:

(BOOL)wasLaunchedByProcess:(NSString*)creator { BOOL wasLaunchedByProcess = NO;

// Get our PSN OSStatus err; ProcessSerialNumber currPSN; err = GetCurrentProcess (&currPSN); if (!err) { // We don’t use ProcessInformationCopyDictionary() because the ‘ParentPSN’ item in the dictionary // has endianness problems in 10.4, fixed in 10.5 however. ProcessInfoRec procInfo; bzero (&procInfo, sizeof (procInfo)); procInfo.processInfoLength = (UInt32)sizeof (ProcessInfoRec); err = GetProcessInformation (&currPSN, &procInfo); if (!err) { ProcessSerialNumber parentPSN = procInfo.processLauncher;
```
// Get info on the launching process
NSDictionary* parentDict = (NSDictionary*)ProcessInformationCopyDictionary (&parentPSN, kProcessDictionaryIncludeAllInformationMask);
  
// Test the creator code of the launching app
if (parentDict) {
  wasLaunchedByProcess = parentDict objectForKey:@"[[FileCreator"] isEqualToString:creator];
  [parentDict release];
}   } }
```
return wasLaunchedByProcess; }
(BOOL)wasLaunchedAsLoginItem { // If the launching process was ‘loginwindow’, we were launched as a login item return [self wasLaunchedByProcess:@”lgnw”]; }

or, you may determine this through an Apple Event:

(void) handleOpenApplicationEvent: (NSAppleEventDescriptor ) event replyEvent: (NSAppleEventDescriptor *) replyEvent { NSAppleEventDescriptor propData = [event paramDescriptorForKeyword: keyAEPropData]; bool startAtLogin = false; DescType type = propData ? [propData descriptorType] : typeNull; OSType value = 0;

if(type == typeType)
{
    value = [propData typeCodeValue];
    startAtLogin = (value == 'lgit'); //keyAELaunchedAsLogInItem
}

NSLog(@"PropDataTypeValue:%i startAtLogin:%i", value, startAtLogin ); }

(void)applicationWillFinishLaunching:(NSNotification *)aNotification { // install event handler [[NSAppleEventManager sharedAppleEventManager] setEventHandler: self andSelector: @selector(handleOpenApplicationEvent:replyEvent:) forEventClass:kCoreEventClass andEventID:kAEOpenApplication];

If you wish to determine if an application is amongst the user’s current login items:

10.4+: use Apple’s LoginItemsAE sample code (not 64 bit clean, deprecated APIs)
10.5+: use the APIs in LaunchServices/LSSharedFileList.h

These are two different tests, since an app can be a login item but still be launched from the Finder.

If you want to add an application to the set of login items, see StartingMyAppOnStartup.

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