Considering that the code you just provided is not even close to what your guidelines were suggestion he do, you just cheated. A program following your guidelines would have looked like the following, which is long winded. And by long-winded, I don't mean code length, I mean that you're doing more work than is necessary (in this case, the overhead of unnecessary file output). Note that I didn't bother with file locking this time around. 

#!c:/perl/bin/perl -w
$|++;

use strict;

print "Enter new student's name: ";
chomp( my $student = <STDIN> );

open my $fh, '<', 'students.dat' or die "open failed: $!";
open my $tmp, '>', 'students.tmp' or die "open failed: $!";

my $found = 0;
while (<$fh>) {
   print $tmp $_;
   $found = 1 if /^\Q$student\E$/i;
}

print $tmp $student, "\n" unless $found;

close $fh;
close $tmp;
rename 'students.tmp', 'students.dat';

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In reply to Re^4: appending to a file by Anonymous Monk
in thread appending to a file by Anonymous Monk

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