Hi ,

I am trying to execute :

system("while true; do echo aabbcc >> $temp_file; sleep 2; done &");
system("tail -f $temp_file >> $file &");

[download]

And then catch the events with the AnyEvent framework. It works but my system calls creates 2 zombie process when I kill my main program. The while and tail -f commands are still executing because the system calls are executing in an other group than my main script. How can I fix this ?

Thank you for your help. Regards

I finally got it working by using : 

$childPid = open SON, "-|";

sub sigtrap() {
    print "\n";
    print("------      Killing all childrens then exeting ...      ---
+---\n");
    if(defined($childPid) && ! ($childPid == 0)){
        killfam 'KILL', ($childPid);
    }
    print "\n";
    print "Exiting ... \n";
    exit(1);
}

if ($childPid) {
    #parent
    system("while true; do echo aabbcc >> $temp_file; sleep 2; done");
}else {
    print "[$$]: Child...\n"; 
    system("tail -f $temp_file >> $file &");
    exit(0);
}

[download]

I finally understood that i needed to use a different process for each infinite running task and that if I wanted to do this in a non blocking mode I should do it on a fork.

Thank you all for your help

In reply to The proper way to execute echo aabbcc >> file in backround by young_monk_love_perl

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