Hey all.. I wrote this script a while back when I couldn't leave telnets to my server open because of my firewall. It's a rather straitforward utility that I leave running in the background. Now, while this is definitely, IMO, a CUFP, it also has a problem and I'm hoping someone here can point out what I'm not seeing.

When I first run the script, it performs perfectly for about a day, but then gets more and more intermittant in its notification deliveries. Eventually, I won't receive a message from it for days, in spite of receiving dozens of emails. Any ideas?
(personal info has been anonymized)


#!/usr/bin/perl -w
# Using Perl 5.005_03 on RedHat 6.2

$MAILFILE1 = "/var/spool/mail/mbox1";
$MAILFILE2 = "/var/spool/mail/mbox2";
$MAILFILE3 = "/var/spool/mail/mbox3";

$current_size1 = (stat $MAILFILE1)[7];
$current_size2 = (stat $MAILFILE2)[7];
$current_size3 = (stat $MAILFILE3)[7];

for (;;) {

   $newsize1 = (stat $MAILFILE1)[7];
   $newsize2 = (stat $MAILFILE2)[7];
   $newsize3 = (stat $MAILFILE3)[7];

   if ( $newsize1 > $current_size1 ) {
      notify("Email Notification", "Mailbox1");
      $current_size1 = $newsize1;
   }
   elsif ( $newsize1 < $current_size1 ) {
      $$current_size1 = $newsize1;
   }
   if ( $newsize2 > $current_size2 ) {
      notify("Email Notification", "Mailbox2");
      $current_size2 = $newsize2;
   }
   elsif ( $newsize2 < $current_size2 ) {
      $current_size2 = $newsize2;
   }
   if ( $newsize3 > $current_size3 ) {
      notify("Email Notification", "Mailbox3");
      $current_size3 = $newsize3;
   }
   elsif ( $newsize3 < $current_size3 ) {
      $current_size3 = $newsize3;
   }
   sleep 30;

}

sub notify {

   $user = $_[1];
   $purpose = $_[0];

   if ( userisonline() ) {

     system "echo \'***** New mail has arrived for $user *****\' | wri
+te myusername";

  }
  else {

     # email notice to 5140490@pager.icq.com

     open (SENDMAIL, "|/usr/sbin/sendmail -t") || OpenError("Sendmail"
+);

     print SENDMAIL "To: Name <5555555\@pager.icq.com>\n";
     print SENDMAIL "From: $purpose <nobody\@cwes.net>\n";
     print SENDMAIL "$purpose for $user\n\n";

     close (SENDMAIL);

  }

}

sub userisonline {

   open (WHO, "who |");
   while (<WHO>) {
      if ( $_ =~ /myusername/ ) {
         close (WHO);
         return 1;
      }
   }
   close (WHO);
   return 0;

}

[download]

Spacewarp

DISCLAIMER:
Use of this advanced computing technology does not imply an endorsement
of Western industrial civilization.

In reply to New Email Notification by spacewarp

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