This manual page is part of the POSIX Programmer's Manual. The Linux
implementation of this interface may differ (consult the corresponding Linux
manual page for details of Linux behavior), or the interface may not be
implemented on Linux.
pthread_self — get the calling thread ID
The pthread_self() function shall return the thread ID of the calling
The pthread_self() function shall always be successful and no return
value is reserved to indicate an error.
No errors are defined.
The following sections are informative.
The pthread_self() function provides a capability similar to the
getpid() function for processes and the rationale is the same: the
creation call does not provide the thread ID to the created thread.
The Base Definitions volume of POSIX.1‐2017,
Portions of this text are reprinted and reproduced in electronic form from IEEE
Std 1003.1-2017, Standard for Information Technology -- Portable Operating
System Interface (POSIX), The Open Group Base Specifications Issue 7, 2018
Edition, Copyright (C) 2018 by the Institute of Electrical and Electronics
Engineers, Inc and The Open Group. In the event of any discrepancy between
this version and the original IEEE and The Open Group Standard, the original
IEEE and The Open Group Standard is the referee document. The original
Standard can be obtained online at http://www.opengroup.org/unix/online.html .
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