NSFileHandle

NSFileHandle *myHandle = [NSFileHandle fileHandleForUpdatingAtPath:appFile];
[myHandle seekToEndOfFile];
[myHandle writeData:data];
[myHandle closeFile];




Maybe better is:
- on App startup:
NSFileHandle *myHandle = [NSFileHandle fileHandleForUpdatingAtPath:appFile];

- on log write
[myHandle seekToEndOfFile];
[myHandle writeData:data];
[myHandle synchronizeFile];

- on App shutdown
[myHandle closeFile];