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这种方法不不能用于 SIGKILL, SIGSTOP, 因为这两个信号不能捕捉，不能忽略。

#include <stdio.h>
#include <signal.h>
#include <pthread.h>
#include <unistd.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>

static struct sigaction siga;

static void multi_handler(int sig, siginfo_t *siginfo, void *context) {
    // get pid of sender,
    pid_t sender_pid = siginfo->si_pid;

    if(sig == SIGINT) {
        printf("INT, from [%d]\n", (int)sender_pid);
        return;
    } else if(sig == SIGQUIT) {
        printf("Quit, bye, from [%d]\n", (int)sender_pid);
        exit(0);
    }

    return;
}


int main(void)
{
    siga.sa_sigaction = *multi_handler;
    siga.sa_flags |= SA_SIGINFO; // get detail info


   // change signal action,
    if(sigaction(SIGINT, &siga, NULL) != 0) {
        printf("error sigaction()");
        return errno;
    }
    if(sigaction(SIGQUIT, &siga, NULL) != 0) {
        printf("error sigaction()");
        return errno;
    }


    while(1)
    {
        sleep(10);
    }
}

测试：

$ ./signal &
[1] 12267

$ kill -2  12267
INT, from [4909]

$ ps aux | grep 4909
charles   4909  0.0  0.2  12340 10120 pts/19   Ss   09:20   0:02 -bash

4096就是 bash的PID