This is probably overkill, but my first thought was, can't you do a system call to the Unix command wc (which can give you the number of lines in your input file?)

And CPAN also has two modules that I think will give you the same functionality.

Otherwise, for the headers, I'm thinking you could just add a variable which keeps track of how many lines you've read in. Then you'd be able to calculate whether you're still dealing with header rows. 
while(<INPUT>) {
  $linecount++ ; 
  next if $linecount <= $numHeaders;

[download]
The footer problem is a bit trickier, but after the header you could first just push every row into an array as a separate string element. Then you'd know exactly how many lines you're dealing with, and you can parse only the elements that lead up to @array[ scalar @array - $numFooters ]

(Updated to remove extraneous parentheses and use scalar on @array)

In reply to Re: More efficient way to exclude footers by Intermediate Dave
in thread More efficient way to exclude footers by babysFirstPerl

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