#!/usr/local/bin/perl
# @(#) edcron  Edit crontab file
# Usage:
# -v        be verbose
# -u user   edit user crontab file
# pat@jaameri.gsfc.nasa.gov (patrick m. ryan)

require 'getopts.pl';
&Getopts('vu:');
	 
$tmpdir = $ENV{TMPDIR} || "/tmp";
$tmp = $tmpdir . "/.crontab.$<.$$";
$edit = $ENV{VISUAL} || $ENV{EDITOR} || "vi";
$user = $opt_u || '';

# put crontab file into a temporary file
$cmd = "crontab -l $user > $tmp";
if ($opt_v) { print $cmd,"\n"; }
system $cmd;
chmod(0600,$tmp);

if ($?>>8) {
    unlink $tmp;
    die "could not execute \"$cmd\"";
}

# edit the temporary crontab file
$mtime = (stat $tmp)[9];
$cmd = "$edit $tmp";
if ($opt_v) { print $cmd,"\n"; }
system $cmd;

if ($?>>8) {
    unlink $tmp;
    die "could not execute \"$cmd\"";
}

unless ((stat $tmp)[9] > $mtime)
{
    print "no change\n";
    exit 0;
}

print "Install modified crontab file? (y/n) ";
$resp = <STDIN>;

$resp =~ s/^\s*//;
unless ($resp eq "" || $resp =~ /^y/i) {
    print "No change\n";
    exit 0;
}

$cmd = "crontab $tmp";
if ($opt_v) { print $cmd,"\n"; }
system $cmd;
if ($?>>8) {
    unlink $tmp;
    die "could not execute \"$cmd\"";
}

unlink $tmp;

exit 0;