Re: Failure to kill pid

[John Lorer <jdl136 mail usask ca>]

John Hawk wrote:
> 
> The code below creates a fork to run grep.
> Code works correctly except for KILL resulting in an inability
> to reuse a grep file search.  The question is why the PID goes Zombie vs
> being killed. Replace the PID with 0 and parent is killed as expected.
> Suggestions ?
> 
[snip]
> void sigchld_handler (gint signal)
> {
>         close (TASK_HANDLE);
>         kill (TASK_PID,9);
>         TASK_WORKING = FALSE;
> }
> 
[snip]

See 'man 2 wait'. If a child process exits before its parent's process
and is not waited, it becomes a zombie. To prevent the zombie, use
wait(NULL); or waitpid(TASK_PID, status, options); after the kill().
Read the man page and decide which waitpid() options you need, and
whether you care you about status.

HTH

jdl