Hi - I need to lauch a background process and get the pid. I had a look at a lot of post and they say to use fork and exec as follows: 
#!/usr/bin/perl
use strict;
use warnings;

my $pid = fork;
if ((defined $pid) && ($pid == 0))
{
    exec("sleep 30 >> /dev/null 2>&1 &");
    exit;
}

print "child pid [$pid]\n";

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However it does not give me the correct pid of the sleep program: 
$ perl tst.pl
child pid [23367]
$ ps ax | grep sleep
23368 pts/7    S      0:00 sleep 30
23371 pts/7    S+     0:00 grep --colour=auto sleep

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How can I a launch a program and get its pid?

In reply to How do you launch a background process and get pid? by bt101

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