Linux多线程之信号2

#include<signal.h>

#include<iostream>

using namespace std;



int alarm_fired;



void ding(int sig)

{

alarm_fired=1;

}



int main()

{

pid_t pid;

cout<<"alarm application start"<<endl;

pid=fork();

if(pid==-1)

{

cout<<"error"<<endl;

exit(1);

}

else if(pid==0)

{

sleep(5);

kill(getppid(),SIGALRM);

exit(0);

}

cout<<"wait for alarm to go off"<<endl;

(void) signal(SIGALRM,ding);

pause();

if(alarm_fired)

cout<<"ding"<<endl;

cout<<"done"<<endl;

exit(0);

}

output:

[xq@m1 ~]$ g++ -o signa_kill signa_kill.cpp

[xq@m1 ~]$ ./signa_kill

alarm application start

wait for alarm to go off

ding

done

[xq@m1 ~]$