noble (2) gettid.2.gz

NAME

       gettid - get thread identification

LIBRARY

       Standard C library (libc, -lc)

SYNOPSIS

       #define _GNU_SOURCE
       #include <unistd.h>

       pid_t gettid(void);

DESCRIPTION

       gettid()  returns  the caller's thread ID (TID).  In a single-threaded process, the thread ID is equal to
       the process ID (PID, as returned by getpid(2)).  In a multithreaded process, all threads  have  the  same
       PID, but each one has a unique TID.  For further details, see the discussion of CLONE_THREAD in clone(2).

RETURN VALUE

       On success, returns the thread ID of the calling thread.

ERRORS

       This call is always successful.

STANDARDS

       Linux.

HISTORY

       Linux 2.4.11, glibc 2.30.

NOTES

       The  thread  ID  returned by this call is not the same thing as a POSIX thread ID (i.e., the opaque value
       returned by pthread_self(3)).

       In a new thread group created by a clone(2) call  that  does  not  specify  the  CLONE_THREAD  flag  (or,
       equivalently, a new process created by fork(2)), the new process is a thread group leader, and its thread
       group ID (the value returned by getpid(2)) is the same as its thread ID (the value returned by gettid()).

SEE ALSO

       capget(2), clone(2), fcntl(2), fork(2), get_robust_list(2), getpid(2), ioprio_set(2), perf_event_open(2),
       sched_setaffinity(2), sched_setparam(2), sched_setscheduler(2), tgkill(2), timer_create(2)