Kill child process spawned with execl without making it zombie

I need to spawn a long-running child process and then kill it from the parent code. At the moment I do like this:

int PID = fork();
if (PID == 0) {
  execl("myexec", "myexec", nullptr);
  perror("ERROR");
  exit(1);
}
// do something in between and then:
kill(PID, SIGKILL);

JavaScript
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int PID = fork();if (PID == 0) {  execl("myexec", "myexec", nullptr);  perror("ERROR");  exit(1);}// do something in between and then:kill(PID, SIGKILL);​

This does the job in the sense that the child process is stopped, but then it remains as a zombie. I tried to completely remove it by adding:

kill(getpid(), SIGCHLD);

JavaScript
 
kill(getpid(), SIGCHLD);​

to no avail. I must be doing something wrong but I can’t figure out what, so any help would be greatly appreciated. Thanks.

Answer

signal(SIGCHLD, SIG_IGN);
kill(getpid(), SIGCHLD);

JavaScript
 
signal(SIGCHLD, SIG_IGN);kill(getpid(), SIGCHLD);​

Presto. No zombie.

By ignoring SIGCHLD we tell the kernel we don’t care about exit codes so the zombies just go away immediately.

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Answer