pthread_self(3) Library Functions Manual pthread_self(3)
NAME
pthread_self - obtain ID of the calling thread
LIBRARY
POSIX threads library (libpthread, -lpthread)
SYNOPSIS
#include <pthread.h>
pthread_t pthread_self(void);
DESCRIPTION
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
This function always succeeds, returning the calling thread's ID.
ERRORS
This function always succeeds.
ATTRIBUTES
For an explanation of the terms used in this section, see attrib-
utes(7).
┌───────────────────────────────────────────┬───────────────┬─────────┐
│ Interface │ Attribute │ Value │
├───────────────────────────────────────────┼───────────────┼─────────┤
│ pthread_self() │ Thread safety │ MT-Safe │
└───────────────────────────────────────────┴───────────────┴─────────┘
STANDARDS
POSIX.1-2008.
HISTORY
POSIX.1-2001.
NOTES
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 de-
tached 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
pthread_create(3), pthread_equal(3), pthreads(7)
Linux man-pages 6.7 2023-10-31 pthread_self(3)
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