The reason unless everything appears dead is once $allcool has been set to false (as it will if any of the processes before or after it don't match $process), there's no way for it to become true again.

Instead, consider inverting your logic so that your state is always false until proved otherwise, like...

my $allcool = 0; # start false
foreach my $psaxline (@psax_list) {
  $allcool++ if ($psaxline =~ /$process/);
}

unless ($allcool) {
  print "$process does not appear to be running!\n";
}
[download]

...or even simpler...

print "$process does not appear to be running!\n"
  unless grep /$process/, @psax_list;
[download]

... which does pretty much the same thing, as grep returns only it's matches, so if there aren't any...

    --k.

Update: markup fixes.