NAME

pthread_cond_timedwait — wait on a condition variable for a specific amount of time

SYNOPSIS

#include <pthread.h>

int
pthread_cond_timedwait(pthread_cond_t *cond, pthread_mutex_t *mutex, const struct timespec *abstime);

DESCRIPTION

The pthread_cond_timedwait() function atomically blocks the current thread waiting on the condition variable specified by cond, and releases the mutex specified by mutex. The waiting thread unblocks only after another thread calls pthread_cond_signal(3), or pthread_cond_broadcast(3) with the same condition variable, or if the system time reaches the time specified in abstime, and the current thread reacquires the lock on mutex.

Values for struct timespec can be obtained by adding the required time interval to the the current time obtained using gettimeofday(2).

Note that struct timeval and struct timespec use different units to specify the time. Hence, the user should always take care to perform the time unit conversions accordingly.

EXAMPLE

struct timeval tv;
struct timespec ts;
gettimeofday(&tv, NULL);
ts.tv_sec = tv.tv_sec + 0;
ts.tv_nsec = 0;

RETURN VALUES

If successful, the pthread_cond_timedwait() function will return zero. Otherwise an error number will be returned to indicate the error.

ERRORS

The pthread_cond_timedwait() function will fail if:

[EINVAL]

The value specified by cond, mutex or abstime is invalid.

[ETIMEDOUT]

The system time has reached or exceeded the time specified in abstime.

SEE ALSO

pthread_cond_broadcast(3), pthread_cond_destroy(3), pthread_cond_init(3), pthread_cond_signal(3), pthread_cond_wait(3), gettimeofday(2)

STANDARDS

The pthread_cond_timedwait() function conforms to ISO/IEC 9945-1:1996 (“POSIX.1”).