I see you already have a few responses, but here's mine anyway: 
#!/usr/bin/perl -w
use strict;

open (IN, "<infile.txt") or die "$!\n";
open (OUT, ">outfile.txt") or die "$!\n";

# Read the entire file into an array
my @lines = <IN>;
close IN;

# An array evaluated in scalar context returns the number of elements
my $numlines = @lines;

# Iterate through the array, stopping at the second last element
# Array indexes start from 0, so we stop at $numlines -2
my $cnt;
for ($cnt=0; $cnt<=$numlines-2; $cnt++) {
    # Do stuff...
    $lines[$cnt] =~ # blah...blah...
}

# Index -1 always refers to the last element
# So process the last line separately here...
$lines[-1] =~ # blah...blah...

# Now, print the lot
print OUT @lines;
close OUT;

[download]

--Darren

In reply to Re: While.For loop noob query by McDarren
in thread While.For loop noob query by jriggs420

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.