NAME

       gettid - get thread identification

SYNOPSIS

       #include <sys/types.h>

       pid_t gettid(void);

       Note: There is no glibc wrapper for this system call; see NOTES.

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 process.

ERRORS

       This call is always successful.

VERSIONS

       The gettid() system call first appeared on Linux in kernel 2.4.11.

CONFORMING TO

       gettid() is Linux-specific and should not be used in programs that are intended to be portable.

NOTES

       Glibc does not provide a wrapper for this system call; call it using syscall(2).

       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 gettid(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), gettid(2), ioprio_set(2), perf_event_open(2),
       sched_setaffinity(2), sched_setparam(2), sched_setscheduler(2), tgkill(2), timer_create(2)

COLOPHON

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