What's failing is something related to my use of Parallel::ForkManager.

Would you be willing to try a manual fork method?

For instance: 

#!/usr/bin/perl
#by Zaxo of perlmonks

my @apps = (
   [qw(/path/to/foo args of foo)],
   [qw(/path/to/bar args of it here)]
);

#to avoid Zombies
$SIG{CHLD} = 'IGNORE';

for (@apps) {
   defined(my $cpid = fork) or die $!;
   $cpid or exec {$_->[0]} @$_ or die $!;
}
exit 0; # the parent

#If the apps don't run as daemons, you may need to have 
#them ignore SIGHUP or else call &POSIX::setsid so that 
#the parent's exit doesn't trigger an early demise of the kids.

[download]
or maybe try the following, remembering to try system(1,$cmd) instead of exec( $cmd) 
#!/usr/bin/perl

my $child=fork(); # Spawn off a child
if ($child>0) {
    #parent
    exec ($app1) || die "Could not exec $app1:$!";
    exit(0); # Should never get here!
} elsif ($child == 0 ) {
   # Child process
    exec ($app2) || die "Could not exec $app2:$!";
    exit(0); # should never get here either
} else {
     die "Could not fork! $!";
}

# Evaluating $! will give you the reason you couldn't 
# spawn the exec'ed process.

[download]
I'm not really a human, but I play one on earth.
Old Perl Programmer Haiku ................... flash japh

In reply to Re^5: Adding parallel processing to a working Perl script by zentara
in thread Adding parallel processing to a working Perl script by Jim

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