sem_timedwait 会被signal的信号唤醒及处理办法

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我是靠谱客的博主安静面包，这篇文章主要介绍sem_timedwait 会被signal的信号唤醒及处理办法，现在分享给大家，希望可以做个参考。

一直都在使用sem_timedwait 函数用来处理超时等待应答.但是突然发现没有收到应答.竟然返回了.查了半天竟然是signal(SIGALRM, ....)的原因.man 了一下 sem_timedwait

RETURN VALUE
All of these functions return 0 on success; on error, the value of the
semaphore is left unchanged, -1 is returned, and errno is set to indi‐
cate the error.

ERRORS
EINTR The call was interrupted by a signal handler; see signal(7).这里说了.确实会被唤醒.没办法只能该程序忽略这个信号

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int  _wait_sem( int  sec, char *pack_str_t)
{
    struct timespec ts;
    int sts;
	sem_t *wSem;
	
	wSem = &jf2414_acksem;

	p_ack_str = pack_str_t;
    ts.tv_sec = time(0) + sec;   //important
    ts.tv_nsec = 0;

    /* Try to lock Semaphore */
    sem_init (wSem, 0, 0);//set sem is 0
	while ( 1 )
	{
	    sts = sem_timedwait(wSem, &ts);
	    if(sts == 0)
		{
	        printf("rec ackn");
	        sem_destroy(wSem);
	        return 0;
	    }
	    else
		{
			if(errno == ETIMEDOUT)
			{
				printf("sem timoutn");
				sem_destroy(wSem);
				return -1;
			}
//			else if(errno == EINTR)
//			{
//				continue;//忽略其它signal信号
//			}
		}
	}
}