Hi Perl Monks, i would like to get the exact same behaviour that i get with $ret = system( "some command"); but in addition i want to get the pid of that command, i been reading about the differences between exec,system and backticks, as i understand none of these is usefull for what i want to do. what worked for me was this:

>...my $ret = undef;
>...my $pid = undef;
>...if( $pid = fork()){
>...>...#here i store the pid in some array for other process
>...}
>...elsif( defined $pid){
>...>...$ret = system($cmd);
>...>...open(my $f,">","/tmp/$$") or die "couldn't write file";
>...>...print $f $ret;
>...>...close($f);
>...>...die;#not sure if this is the proper way to kill the child, not
+ my main worry in this question
>...}
>...else{
>...>...print "\n couldnīt fork\n";
>...}

>...waitpid($pid,0);
>...if( open(my $F, "/tmp/$pid")){
>...>...while( my $line = <$F>){
>...>...>...$ret .= $line;
>...>...}
>...>...close($F);
>...>...system("rm /tmp/$pid");
>...}
>...else{
>...>...$ret = -1;
>...}

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i know this is suuper awfull, so mi question is: how i do this properly? p.s: sorry my english, and be good, this is my first question here.

p.s 2: i think the get_pidof function wont do because there will be several identical commands running at the same time.

In reply to get same return that system gives and get pid by Raiden690

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