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pthread_self(3) — Linux manual page

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | ATTRIBUTES | STANDARDS | HISTORY | NOTES | SEE ALSO | COLOPHON 

pthread_self(3)          Library Functions Manual         pthread_self(3)

NAME         top

       pthread_self - obtain ID of the calling thread

LIBRARY         top

       POSIX threads library (libpthread, -lpthread)

SYNOPSIS         top

       #include <pthread.h>

       pthread_t pthread_self(void);

DESCRIPTION         top

       The pthread_self() function returns the ID of the calling thread.
       This is the same value that is returned in *thread in the
       pthread_create(3) call that created this thread.

RETURN VALUE         top

       This function always succeeds, returning the calling thread's ID.

ERRORS         top

       This function always succeeds.

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).
       โ”Œโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ฌโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ฌโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”
       โ”‚ Interface                            โ”‚ Attribute     โ”‚ Value   โ”‚
       โ”œโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ผโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ผโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ค
       โ”‚ pthread_self()                       โ”‚ Thread safety โ”‚ MT-Safe โ”‚
       โ””โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ดโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ดโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”˜

STANDARDS         top

       POSIX.1-2008.

HISTORY         top

       POSIX.1-2001.

NOTES         top

       POSIX.1 allows an implementation wide freedom in choosing the type
       used to represent a thread ID; for example, representation using
       either an arithmetic type or a structure is permitted.  Therefore,
       variables of type pthread_t can't portably be compared using the C
       equality operator (==); use pthread_equal(3) instead.

       Thread identifiers should be considered opaque: any attempt to use
       a thread ID other than in pthreads calls is nonportable and can
       lead to unspecified results.

       Thread IDs are guaranteed to be unique only within a process.  A
       thread ID may be reused after a terminated thread has been joined,
       or a detached thread has terminated.

       The thread ID returned by pthread_self() is not the same thing as
       the kernel thread ID returned by a call to gettid(2).

SEE ALSO         top

       pthread_create(3), pthread_equal(3), pthreads(7)

COLOPHON         top

       This page is part of the man-pages (Linux kernel and C library
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       the project can be found at 
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       for this manual page, see
       โŸจhttps://git.kernel.org/pub/scm/docs/man-pages/man-pages.git/tree/CONTRIBUTINGโŸฉ.
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       man-pages@man7.org

Linux man-pages 6.18            2025-05-17                pthread_self(3)

Pages that refer to this page: gettid(2),  pthread_create(3),  pthread_equal(3),  pthread_getcpuclockid(3),  pthread_kill(3),  pthread_setaffinity_np(3),  pthread_setschedparam(3),  pthread_setschedprio(3),  pthreads(7),  signal-safety(7)

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