I know, this thread is very old. Having read all above posts, I would like to add one more idea to handle this in a neat way: If you get into the mapping business anyway (mapping pthread_to to an int), you could as well go one step further in readability. Make your pthread_create_wrapper such that it takes a string, too...the name of the thread. I learned to appreciate this "SetThreadName()" feature on windows and windows CE. Advantages: Your ids are not just numbers but you also see, which of your threads has which purpose.