cocoa - NSLog 10b meaning?

Question

Whenever I use NSLog(), it always shows this mysterious "10b" next to the process ID. I know that this is tied somehow to the thread where the NSLog() call was made, but what exactly does it mean? When I try NSLog() from a different thread in the same process, I will get values like 1003, 1103, and 1403. Here is the "Hello, World!" output or NSLog() for reference:

2009-09-15 10:26:38.591 delme[38163:10b] Hello, World!

Answer 1

It’s the thread ID; specifically, it’s the mach thread ID. You can get it yourself:

pthread_mach_thread_np(pthread_self())