I've read a variety of docs and examples for how to fork processes, how to get the child pid, and how to kill a pid. I haven't found the right example that illustrates what I wish to accomplish.

My platform is redhat. What I'm attempting to accomplish is this:

fork this process to the background "tcpdump -ni int0 -c 5 -w /tmp/somefile"

sleep while the child process completes, or kill it if it is running longer than 10 seconds ( eg: tcpdump doesn't capture any data ).

my sample code looks like this:

use POSIX;
$SIG{CHLD} = 'IGNORE';
my $snoop = fork();
if ( $snoop == 0 ){
    setpgrp;
    system("tcpdump -ni int0 -c 5 -w /tmp/somefile &");
}

my $sleeper = 0;
while ( $sleeper < 11 ){
    # How do I check the status of my child pid? I don't want to wait 
+for it to finish, just know if it is still running and 'last;' if not
+.
    sleep 1;
    $sleeper++
}

# Only kill the child pid, if it is running. need help here.
kill -1, getpgrp($snoop);
# continue on with my code

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I should add, that I don't have an option for using specific perl modules to enhance by capabilities here.

In reply to forking, waiting, and killing child pids by sinmissing

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