rt_sem_trywait(2)

NAME

rt_sem_trywait - semaphore 'wait' operation (without blocking)

SYNOPSIS

#define MODULE
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/version.h>
#include <linux/errno.h>
#include rt_ipc.h

int rt_sem_trywait(rt_sem_t *sem);

DESCRIPTION

rt_sem_wait is the semaphore wait (sometimes known as 'take' or 'P') operation. Unlike rt_sem_wait, rt_sem_trywait returns immediately whether or not the semaphore is available. sem points to the structure used in the call to rt_sem_create.

RETURN VALUE

On success, 0 is returned. On failure, a negative value is returned as described below.

ERRORS

-EAGAIN: the semaphore is not currently available.

-EINVAL: sem does not point to a valid rt_sem_t.

AUTHOR

Jerry Epplin <[email protected]>