#!/usr/bin/perl

use strict;
use warnings;

if (scalar @ARGV != 1) {
    die "Usage: strip-trailing-linefeed.pl <filename>\n";
}

my $filename = $ARGV[0];

open(IN, "<$filename");
my $count = 0;

my $line;

while (<IN>) {
    $count++;
    $line = $_;
}
close(IN);

if ($count != 1) {
    die "$filename has not exactly 1 line ... doing nothing\n";
}

$line =~ s/[\n\r]+$//;

open(OUT, ">$filename");
print OUT $line;
close(OUT);