p8-8.c

SUN Solaris8平台下进程间通信

#include <signal.h>
/* 该标志在 SIGALRM 信号句柄中被设置. */
volatile sig_atomic_t flag = 0;
int main (void)
{
    sigset_t block_alarm;
    /* 初始信号屏蔽 */
    sigemptyset (&block_alarm);
    sigaddset (&block_alarm, SIGALRM);              /* 要屏蔽的信号是SIGALRM */
    while (1){
        sigprocmask (SIG_BLOCK, &block_alarm, NULL);            /* 设置屏蔽 */
        if (flag){                      /* 检查信号到达否,若到达则清除标志flag  */         
            ACTIONS-IF-ARRIVED
            flag = 0;
        }
        sigprocmask (SIG_UNBLOCK, &block_alarm, NULL);          /* 解除屏蔽 */   
        ...
    }
}