如何从父进程向孩子发出信号？

Question

How can i send signal from parent process to the child? After i write to the pipe i want to send signal to the child process.

 pid_t pid;
     int filds[2];
     pipe(filds);
     char *args[150] = {"./draw.out", NULL};
     char buff = '\0';

     if ((pid = fork()) < 0) {  // fork a child process/
         printf("*** ERROR: forking child process failed\n");
         exit(1);
     } else if (pid == 0) {
         execvp(args[0], args); // execute the command
     } else {  // for the parent
         char btnPressed = getch();

         while (btnPressed != 'q'){
             btnPressed = getch();
             write(filds[1],buff, BUFF_SIZE); 
             //signal
         }
         // signal finish game.
     }

Answer 1

kill(PID, SIGwhatever);

however this is probably a poor choice; the better solution is

close(filds[1]);

and handle close of input in the child. I think you're missing a

dup2(files[0],0);

in the child path as well.