Is this what you are looking for? 
use strict;
use warnings;
use Tie::File;

# usage: perl script.pl [file1] [file2] [...]

foreach my $file (grep { -f } @ARGV) {

    tie my @file, 'Tie::File', $file
      or die "Can't tie into file $file: $!";

    my $regex = qr/\sSIL\s*\z/;

    foreach my $i (reverse 0 .. $#file) {
        if ($file[$i] =~ /$regex/) {
            1 while ($file[--$i] =~ /$regex/);
            print "$file[$i + 1]\n";
            $#file = $i + 1;
            last;
        }
    }

    untie @file;
}

[download]

In reply to Re: removing lines that are in the end of a file by trizen
in thread removing lines that are in the end of a file by bhargavkanakiya

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.