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sem_post(3) [centos man page]

SEM_POST(3)						     Linux Programmer's Manual						       SEM_POST(3)

NAME
sem_post - unlock a semaphore SYNOPSIS
#include <semaphore.h> int sem_post(sem_t *sem); Link with -pthread. DESCRIPTION
sem_post() increments (unlocks) the semaphore pointed to by sem. If the semaphore's value consequently becomes greater than zero, then another process or thread blocked in a sem_wait(3) call will be woken up and proceed to lock the semaphore. RETURN VALUE
sem_post() returns 0 on success; on error, the value of the semaphore is left unchanged, -1 is returned, and errno is set to indicate the error. ERRORS
EINVAL sem is not a valid semaphore. EOVERFLOW The maximum allowable value for a semaphore would be exceeded. CONFORMING TO
POSIX.1-2001. NOTES
sem_post() is async-signal-safe: it may be safely called within a signal handler. EXAMPLE
See sem_wait(3). SEE ALSO
sem_getvalue(3), sem_wait(3), sem_overview(7) COLOPHON
This page is part of release 3.53 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/. Linux 2012-05-13 SEM_POST(3)

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SEM_POST(3)						     Linux Programmer's Manual						       SEM_POST(3)

NAME
sem_post - unlock a semaphore SYNOPSIS
#include <semaphore.h> int sem_post(sem_t *sem); Link with -pthread. DESCRIPTION
sem_post() increments (unlocks) the semaphore pointed to by sem. If the semaphore's value consequently becomes greater than zero, then another process or thread blocked in a sem_wait(3) call will be woken up and proceed to lock the semaphore. RETURN VALUE
sem_post() returns 0 on success; on error, the value of the semaphore is left unchanged, -1 is returned, and errno is set to indicate the error. ERRORS
EINVAL sem is not a valid semaphore. EOVERFLOW The maximum allowable value for a semaphore would be exceeded. ATTRIBUTES
For an explanation of the terms used in this section, see attributes(7). +-----------+---------------+---------+ |Interface | Attribute | Value | +-----------+---------------+---------+ |sem_post() | Thread safety | MT-Safe | +-----------+---------------+---------+ CONFORMING TO
POSIX.1-2001. NOTES
sem_post() is async-signal-safe: it may be safely called within a signal handler. EXAMPLE
See sem_wait(3). SEE ALSO
sem_getvalue(3), sem_wait(3), sem_overview(7), signal-safety(7) COLOPHON
This page is part of release 4.15 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/. Linux 2017-03-13 SEM_POST(3)
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