11-4.c

《linux应用开发技术详解》的配套代码

 #include<unistd.h>
  #include<signal.h>
  void show_handler(struct sigaction * act)
  {
     switch (act->sa_flags)
          {
            case SIG_DFL:
               {
                 printf(“Default action\n”);
                 break;
              }
           case SIG_IGN:
               {
                 printf(“Ignore the signal\n”);
                 break;
               }  
            default:
              {
                 printf(“0x%x\n”,act->sa_handler);
             }  
         }
  }
  main()
   {
      int i;
      struct sigaction act,oldact;
      act.sa_handler = show_handler;
      act.sa_flags = SA_ONESHOT|SA_NOMASK;
      sigaction(SIGUSR1,&act,&oldact);
      for(i=5;i<15;i++)
       {
         printf(“sa_handler of signal %2d =”.i);
          sigaction(i,NULL,&oldact);
       }
   }