sema_post(SYNCH)
sema_post --
release a lock by incrementing the count value of the semaphore
Synopsis
cc [options] -Kthread file
#include <synch.h>
int sema_post(sema_t *sema);
Description
sema_post increments the count
of the semaphore pointed to by sema,
and if the new count value is less than or equal to zero,
makes the next thread waiting at the semaphore runnable.
If more than one thread is waiting,
release from the blocked group is scheduling policy-specific for
bound threads, and might be dependent on scheduling parameters
for multiplexed threads.
Parameters
sema-
pointer to the semaphore to increment
sema parameter
sema must previously have been initialized,
either by sema_init or statically (see sema_init(SYNCH)).
Return values
sema_post returns zero for success
and an error number for failure.
Errors
If the following condition is detected,
sema_post returns the corresponding value:
EINVAL-
invalid argument specified
References
Intro(SYNCH),
semaphore(SYNCH),
sema_destroy(SYNCH),
sema_init(SYNCH),
sema_trywait(SYNCH),
sema_wait(SYNCH)
© 2005 The SCO Group, Inc. All rights reserved.
SCO OpenServer Release 6.0.0 - 01 June 2005