pthread_tryjoin_np (3) - Linux Manuals
pthread_tryjoin_np: try to join with a
NAME
pthread_tryjoin_np, pthread_timedjoin_np - try to join with a terminated thread
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.
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 {
pthread_timedjoin_np()
can in addition fail with the following errors:
pthread_timedjoin_np()
never returns the error
EINTR.
struct timespec ts;
int s;
...
if (clock_gettime(CLOCK_REALTIME, &ts) == -1) {
ts.tv_sec += 5;
s = pthread_timedjoin_np(thread, NULL, &ts);
if (s != 0) {
RETURN VALUE
On success,
these functions return 0;
on error, they return an error number.
ERRORS
These functions can fail with the same errors as
pthread_join(3).
pthread_tryjoin_np()
can in addition fail with the following error:
VERSIONS
These functions first appeared in glibc in version 2.3.3.
ATTRIBUTES
For an explanation of the terms used in this section, see
attributes(7).
Interface Attribute Value
pthread_tryjoin_np(),
pthread_timedjoin_np()
Thread safety MT-Safe CONFORMING TO
These functions are nonstandard GNU extensions;
hence the suffix "_np" (nonportable) in the names.
EXAMPLES
The following code waits to join for up to 5 seconds:
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.
COLOPHON
This page is part of release 5.10 of the Linux
man-pages
project.
A description of the project,
information about reporting bugs,
and the latest version of this page,
can be found at
https://www.kernel.org/doc/man-pages/.