Section: POSIX Programmer's Manual (3P)
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.
--- get and set the clock selection condition variable attribute
int pthread_condattr_getclock(const pthread_condattr_t *restrict attr,
clockid_t *restrict clock_id);
int pthread_condattr_setclock(pthread_condattr_t *attr,
function shall obtain the value of the
attribute from the attributes object referenced by
function shall set the
attribute in an initialized attributes object referenced by
is called with a
argument that refers to a CPU-time clock, the call shall fail.
attribute is the clock ID of the clock that shall be used to
measure the timeout service of
The default value of the
attribute shall refer to the system clock.
The behavior is undefined if the value specified by the
does not refer to an initialized condition variable attributes object.
If successful, the
function shall return zero and store the value of the clock attribute
into the object referenced by the
argument. Otherwise, an error number shall be returned to indicate the
If successful, the
function shall return zero; otherwise, an error number shall be
returned to indicate the error.
function may fail if:
The value specified by
does not refer to a known clock, or is a CPU-time clock.
These functions shall not return an error code of
The following sections are informative.
If an implementation detects that the value specified by the
does not refer to an initialized condition variable attributes object,
it is recommended that the function should fail and report an
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
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