sem_timedwait 会被signal的信号唤醒及处理办法

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

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 ack\n");
sem_destroy(wSem);
return 0;
}
else
{
if(errno == ETIMEDOUT)
{
printf("sem timout\n");
sem_destroy(wSem);
return -1;
}
// else if(errno == EINTR)
// {
// continue;//忽略其它signal信号
// }
}
}
}