rt_sem_post.2

rtlinux(realtime linix)3.0,在kernel2.2.18上编译运行

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.TH RT_SEM_POST 2 "21 July 1997" "rt_ipc" "rt_ipc"
.SH NAME
rt_sem_post \- semaphore 'post' operation
.SH SYNOPSIS
.nf
.B #define MODULE
.B #include <linux/module.h> 
.B #include <linux/kernel.h> 
.B #include <linux/version.h> 
.B #include <linux/errno.h> 
.B #include "rt_ipc.h"
.fi
.sp
.BI "int rt_sem_post(rt_sem_t *" sem ");
.SH DESCRIPTION
.B rt_sem_post
is the semaphore post (sometimes known as 'give', 'signal', or 'V') operation.
If tasks are waiting for the semaphore, the one with the highest priority
is allowed to run.
.I sem
points to the structure used in the call to
.BR rt_sem_create .
.SH "RETURN VALUE"
On success, 0 is returned.  On failure, a negative value is returned
as described below.
.SH ERRORS
.IP \fB-EINVAL\fP
.I sem
does not point to a valid rt_sem_t.
.SH "AUTHOR"
Jerry Epplin <[e-mail]>
.SH "SEE ALSO"
.BR rt_task_ipc_delete (2), 
.BR rt_task_ipc_init (2), 
.BR rt_sem_destroy (2), 
.BR rt_sem_init (2), 
.BR rt_sem_trywait (2), 
.BR rt_sem_wait (2)