signal_1.c

工ARM＿LINUX的几个源代码

#include <stdio.h>
#include <signal.h>
#include <unistd.h>
void waiting( ),stop( );
int wait_mark;
main( )
{
     int p1,p2,stdout;
     while((p1=fork( ))= =-1);       /*创建子进程p1*/
     if (p1>0)
            {
                while((p2=fork( ))= =-1);     /*创建子进程p2*/
                if(p2>0)
                     {
                        wait_mark=1;
                        signal(SIGINT,stop);   /*接收到^c信号，转stop*/
                        waiting( );
                        kill(p1,16);        /*向p1发软中断信号16*/
                        kill(p2,17);        /*向p2发软中断信号17*/
                        wait(0);           /*同步*/
                        wait(0);
                        printf("Parent process is killed!/n");
                        exit(0);
                      }
              else
                    {
                       wait_mark=1;
                       signal(17,stop);   /*接收到软中断信号17，转stop*/
                       waiting();
                       lockf(stdout,1,0);
                       printf("Child process 2 is killed by parent!/n");
                       lockf(stdout,0,0);
                       exit(0);
                    }
           }
    else
           {
              wait_mark=1;
              signal(16,stop);        /*接收到软中断信号16，转stop*/
              waiting( );
              lockf(stdout,1,0);
              printf("Child process 1 is killed by parent!/n");
              lockf(stdout,0,0);
              exit(0);
           }
}
 
void waiting( )
{
 while(wait_mark!=0);
}
 
void stop( )
{
wait_mark=0;
}