sem_post(3) 맨 페이지 - 윈디하나의 솔라나라

개요

섹션
맨 페이지 이름
검색(S)

sem_post(3)

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).

       allbox;  lb  lb  lb  l  l  l.   Interface Attribute Value T{ sem_post()
       T}   Thread safety MT-Safe

CONFORMING TO
       POSIX.1-2001.

NOTES
       sem_post() is async-signal-safe: it may be safely called within a  sig‐
       nal 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 5.02 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)
맨 페이지 내용의 저작권은 맨 페이지 작성자에게 있습니다.
RSS ATOM XHTML 5 CSS3