if the file isn't big, read it all in an array, then when you find your match, save your location, and retrieve it directly from the array..

Update:Here it is, completely untested for bugs: 


# assuming the file is already opened and has a <IN> filehandle

my @temp;

# and assuming that you won't match before the first 5 lines..

while (my $line = <IN>) {
    push @temp, $line;
    shift @temp if (scalar @temp > 5);
    if ($line =~ /foo/) { 
        # we've got a match.
        print $temp[0];
    }
}

[download]

Update 2: This looks like davorg's more elegant solution.

He who asks will be a fool for five minutes, but he who doesn't ask will remain a fool for life.

Chady | http://chady.net/

In reply to Re: print line 5 lines previous to comaprison line! by Chady
in thread print line 5 lines previous to comaprison line! by pat

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.