#!/usr/bin/perl
# $Id: back,v 1.1 2005/05/02 07:04:36 michael Exp michael $
# Create a backup of a file

use POSIX;

# get name of file to back up
my $filename = shift;
die "Must supply file name" if (!$filename);

# move the file to filename.YYYYmmdd
# (or filename.YYYYmmdd"T"HHMMSS if that exists)
$mtime = (stat($filename))[9];
$suffix = strftime("%Y%m%d", localtime($mtime));
$dest = "${filename}.${suffix}";
$suffix = strftime("%Y%m%dT%H%M%S", localtime($mtime)) if (-e $dest);
$dest = "${filename}.${suffix}";
die "Backup file $dest already exists" if (-e $dest);

# do the move
rename($filename, $dest);