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   pthread_timedjoin_np    ( 3 )

попытаться присоединиться к завершенному потоку (try to join with a terminated thread)

Имя (Name)

pthread_tryjoin_np, pthread_timedjoin_np - try to join with a
       terminated thread

Синопсис (Synopsis)

#define _GNU_SOURCE             /* See feature_test_macros(7) */
       #include <pthread.h>

int pthread_tryjoin_np(pthread_t thread, void **retval); int pthread_timedjoin_np(pthread_t thread, void **retval, const struct timespec *abstime);

Compile and link with -pthread.


Описание (Description)

These functions operate in the same way as pthread_join(3),
       except for the differences described on this page.

The pthread_tryjoin_np() function performs a nonblocking join with the thread thread, returning the exit status of the thread in *retval. If thread has not yet terminated, then instead of blocking, as is done by pthread_join(3), the call returns an error.

The pthread_timedjoin_np() function performs a join-with-timeout. If thread has not yet terminated, then the call blocks until a maximum time, specified in abstime, measured against the CLOCK_REALTIME clock. If the timeout expires before thread terminates, the call returns an error. The abstime argument is a structure of the following form, specifying an absolute time measured since the Epoch (see time(2)):

struct timespec { time_t tv_sec; /* seconds */ long tv_nsec; /* nanoseconds */ };


Возвращаемое значение (Return value)

On success, these functions return 0; on error, they return an
       error number.

Ошибки (Error)

These functions can fail with the same errors as pthread_join(3).
       pthread_tryjoin_np() can in addition fail with the following
       error:

EBUSY thread had not yet terminated at the time of the call.

pthread_timedjoin_np() can in addition fail with the following errors:

EINVAL abstime value is invalid (tv_sec is less than 0 or tv_nsec is greater than 1e9).

ETIMEDOUT The call timed out before thread terminated.

pthread_timedjoin_np() never returns the error EINTR.


Версии (Versions)

These functions first appeared in glibc in version 2.3.3.

Атрибуты (Attributes)

For an explanation of the terms used in this section, see
       attributes(7).

┌──────────────────────────────────────┬───────────────┬─────────┐ │Interface Attribute Value │ ├──────────────────────────────────────┼───────────────┼─────────┤ │pthread_tryjoin_np(), │ Thread safety │ MT-Safe │ │pthread_timedjoin_np() │ │ │ └──────────────────────────────────────┴───────────────┴─────────┘


Стандарты (Conforming to)

These functions are nonstandard GNU extensions; hence the suffix
       "_np" (nonportable) in the names.

Ошибки (баги) (Bugs)

The pthread_timedjoin_np() function measures time by internally
       calculating a relative sleep interval that is then measured
       against the CLOCK_MONOTONIC clock instead of the CLOCK_REALTIME
       clock.  Consequently, the timeout is unaffected by discontinuous
       changes to the CLOCK_REALTIME clock.

Примеры (Examples)

The following code waits to join for up to 5 seconds:

struct timespec ts; int s;

...

if (clock_gettime(CLOCK_REALTIME, &ts) == -1) { /* Handle error */ }

ts.tv_sec += 5;

s = pthread_timedjoin_np(thread, NULL, &ts); if (s != 0) { /* Handle error */ }


Смотри также (See also)

clock_gettime(2), pthread_exit(3), pthread_join(3), pthreads(7)