$ cat run.sh 
#!/bin/sh

S=p1.pl && p1.pl && S=p2.pl && p2.pl && S=p3.pl && p3.pl

if [ $? = 0 ] 
then
        echo "all completed ok"
else
        echo "$S failed"
fi 

$ cat p?.pl
#!/usr/bin/perl

#exit with no error
exit 0;
#!/usr/bin/perl

# exit with error
exit 1;
#!/usr/bin/perl

#exit with no error
exit 0;

$ ./run.sh 
p2.pl failed
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# untested

@perlscripts = qw[1.pl 2.pl 3.pl];

foreach my $perlscript (@perlscripts)
{
  system($perlscript);

  if($? == -1)
  {
     warn "Couldn't start $perlscript: $!";
  }
  elsif($? != 0)
  {
     warn "Perl script $perlscript exited with: ". 
           $? >> 8
  }
}
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open(<FH>, ">logfile.txt") || die "Doh: $!";
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print FH "warning message";
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If I wanted to replace the warn functions with a function that would write the same output to an error log, what would that look like? Thanks.

If you aren't using your STDERR for anything else, just redirect it to the file and the warnings will show up there. You can do that in your shell script with foo.pl 2>> errlog.txt, or in Perl with:

open STDERR, ">errlog.txt"
  or die "Whoa! I can't even log my errors: $!";
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Otherwise, you'll want the __WARN__ pseudo-signal:

open ERRLOG, ">errlog.txt" or die;
$SIG{__WARN__} = sub {
  my ($msg) = @_;
  $msg ||= q{Warning: something's wrong};

  # Add the file and line number to $msg here
  # using the return values from caller().

  print ERRLOG, $msg;
};
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See also warn and caller in perlfunc and %SIG in perlvar.

-- 
LP^>

You could also put these scripts in modular form. tachyon has written a tutorial which should help explain this.