cnd_timedwait

 

C

Language

Headers

Type support

Program utilities

Variadic function support

Error handling

Dynamic memory management

Strings library

Algorithms

Numerics

Date and time utilities

Input/output support

Localization support

Concurrency support (C11)

Technical Specifications

Symbol index

 

Concurrency support library

Threads thrd_create thrd_equal thrd_current    thrd_sleep thrd_yield thrd_exit thrd_detach thrd_join thrd_successthrd_timedoutthrd_busythrd_nomemthrd_error    Atomic operations atomic_init ATOMIC_VAR_INIT (until C23) ATOMIC_***_LOCK_FREE atomic_is_lock_free atomic_store atomic_load atomic_exchange atomic_compare_exchange atomic_fetch_add atomic_fetch_sub atomic_fetch_or atomic_fetch_xor atomic_fetch_and

Atomic flags atomic_flag ATOMIC_FLAG_INIT atomic_flag_test_and_set atomic_flag_clear Memory ordering memory_order kill_dependency atomic_thread_fence atomic_signal_fence Mutual exclusion mtx_init mtx_lock mtx_timedlock mtx_trylock call_once mtx_unlock mtx_destroy mtx_plainmtx_recursivemtx_timed Condition variables cnd_init cnd_signal cnd_broadcast cnd_wait cnd_timedwait cnd_destroy Thread-local storage thread_local TSS_DTOR_ITERATIONS    tss_create tss_get tss_set tss_delete

 

Defined in header <threads.h>
int cnd_timedwait( cnd_t* restrict cond, mtx_t* restrict mutex,                    const struct timespec* restrict time_point );		(since C11)

Atomically unlocks the mutex pointed to by mutex and blocks on the condition variable pointed to by cond until the thread is signalled by cnd_signal or cnd_broadcast, or until the TIME_UTC based time point pointed to by time_point has been reached, or until a spurious wake-up occurs. The mutex is locked again before the function returns.

The behavior is undefined if the mutex is not already locked by the calling thread.

Parameters

cond	-	pointer to the condition variable to block on
mutex	-	pointer to the mutex to unlock for the duration of the block
time_point	-	pointer to a object specifying timeout time to wait until

Return value

thrd_success if successful, thrd_timedout if the timeout time has been reached before the mutex is locked, or thrd_error if an error occurred.

References

• C17 standard (ISO/IEC 9899:2018):

• 7.26.3.5 The cnd_timedwait function (p: 276-277)

• C11 standard (ISO/IEC 9899:2011):

• 7.26.3.5 The cnd_timedwait function (p: 379-380)

See also

cnd_wait (C11)	blocks on a condition variable (function)
C++ documentation for condition_variable::wait_until
C++ documentation for condition_variable_any::wait_until