Dear Monk,

I have written a crontab Perl program to check whether the company website is available for the customers. We would like to know if there is a problem before the users call to report it.

My code is running on Perl 5.6.1 under RedHat Linux AS v2.1. I am using lwp-request to hit the website.

I am finding that the response time varies at certain times of the day and my timeout causes false failures. I have increased the timeout, but I would like to capture the HTTP error code and know whether it is a timeout or something else.

Here is the code. Thanks in advance! 

#!/usr/bin/perl -w
#       /usr/local/bin/webalert.pl [mail address] [web address]
use strict;
use LWP;
local *MAIL;

# get the mail address if there is one.
my $mailaddr = shift @ARGV;

# get the web address if there is one.
my $webaddr = (shift @ARGV ||"www.perlmonks.org");

my $timeout = 15;
if (system "/usr/bin/lwp-request -t $timeout $webaddr >/dev/null 2>&1"
+) {
  sendmail_or_print()
  }

sub sendmail_or_print {

  # get the mail address if there is one.
  my $hostname = "from ". (`hostname 2>/dev/null` ||"who");

  # get the mail address if there is one.
  if ($mailaddr) {
    open MAIL, "|mail -s \"Web Alert $hostname\" $mailaddr";
    }
  else {
    open MAIL, ">&STDOUT";
    }

  print MAIL "\n\n$webaddr NOT available: " . localtime() ."\n\n";
  print MAIL "$timeout second timeout used.\n\n";
  close MAIL;
  }

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In reply to website availability ping by Lhamo Latso

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