How to get thread id of a pthread in linux c program?

What? The person asked for Linux specific, and the equivalent of getpid(). Not BSD or Apple. The answer is gettid() and returns an integral type. You will have to call it using syscall(), like this:

#include <sys/types.h>
#include <unistd.h>
#include <sys/syscall.h>


 pid_t x = syscall(__NR_gettid);

While this may not be portable to non-linux systems, the threadid is directly comparable and very fast to acquire. It can be printed (such as for LOGs) like a normal integer.

Leave a Comment