in reply to Re^4: Synchronizing Multiple System Processes
in thread Synchronizing Multiple System Processes

If script1.pl returned without having finished creating output.txt, then it didn't create that file.

What happens if you explicitly close the filehandle for output.txt in script1.pl? 

    close OUT or die "Can't close filehandle OUT properly: $!\n";

[download]

--shmem 

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}

In Section Seekers of Perl Wisdom