pthread_condattr_getclock

, pthread_condattr_setclock

- get and set the clock selection condition variable attribute

Synopsis

cc -mt [ flag... ] file... [ library... ]
#include <pthread.h>

int pthread_condattr_getclock(
     const pthread_condattr_t *restrict attr,
     clockid_t *restrict clock_id);

int pthread_condattr_setclock(pthread_condattr_t *attr
      clockid_t clock_id);

Description

The pthread_condattr_getclock() function obtains the value of the clock attribute from the attributes object referenced by attr. The pthread_condattr_setclock() function sets the clock attribute in an initialized attributes object referenced by attr. If pthread_condattr_setclock() is called with a clock_id argument that refers to a CPU-time clock, the call fails.

The clock attribute is the clock ID of the clock that is used to measure the timeout service of pthread_cond_timedwait(3C). The default value of the clock attribute refers to the system clock.

Return Values

Upon successful completion, the pthread_condattr_getclock() function returns 0 and stores the value of the clock attribute of attr into the object referenced by the clock_id argument. Otherwise, an error number is returned to indicate the error.

Upon successful completion, the pthread_condattr_setclock() function returns 0. Otherwise, an error number is returned to indicate the error.

Errors

These functions may fail if:

EINVAL

The value specified by attr is invalid.

The pthread_condattr_setclock() function may fail if:

EINVAL

The value specified by clock_id does not refer to a known clock, or is a CPU-time clock.

Attributes

See attributes(5) for descriptions of the following attributes:

See Also

pthread_cond_init(3C), pthread_cond_timedwait(3C), pthread_condattr_destroy(3C), pthread_condattr_getpshared(3C), pthread_create(3C), pthread_mutex_init(3C), attributes(5), standards(5)