#!/usr/bin/perl

use strict;

my @buf = <DATA>;

for my $i ( 0 .. $#buf ) {
  if ($buf[$i] =~ s/^\s*<jobnumber>(.*)<\/jobnumber>\s*$/$1/s) {
    $buf[$i+1] =~ s/^\s*<location>\s*(.*)\s<location>\s*$/$1/s; 
      # if your tags are really like this
    &process($buf[$i],$buf[$i+1]);
  }
}

sub process {
  my ($jobnumber,$location) = @_; 
  print "Found a job $jobnumber in $location.\n"; # do something
}
__DATA__
  <posts>
    <post>
      <jobnumber>
	      1234
      </jobnumber>
      <location>Somecity, NJ</location>
    </post>
    <post>
      <jobnumber>87922</jobnumber>
      <location>Othercity, AK</location>
    </post>
  </posts>