If you're asking how to take a file and pad all of the lines out to the same width, this piece might work for you (untested): 
#!/usr/bin/perl -w

open(FILE, "+</tmp/foo.txt") || die "Can't open: $!";
$l=0;
@lines=map { chomp;$l=$l<length()?length():$l;$_ } <FILE>;
seek(FILE, 0, 0) || warn "Seek: $!";

for(@lines) {
        printf FILE "%-${l}s\n", $_;
}

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In reply to Re: padding variable length documents by clintp
in thread padding variable length documents by Anonymous Monk

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