#!/usr/bin/perl -w
# vim: set sw=4 ts=4 si et: 
# 
my $status = 0;
my $expr;
($expr = shift) || &help;
&help if ($expr eq "-h");
&help unless (@ARGV);
my @ltime = localtime;
my $date=sprintf("%02d%02d%02d",1900 + $ltime[5] - 2000,$ltime[4] + 1,$ltime[3]);
for (@ARGV) {
    $was = $_;
    eval $expr;
    die $@ if $@;
    if ($was ne $_) {
        if (-e "$_" ){
            print STDERR "ERROR: file $_ does already exist\n";
            $status = 1;
            next;
        }
        unless (rename($was, $_)) {
            print STDERR "$0: can't rename $was to $_: $!\n";
            $status = 1;
        }
    } 
}
exit $status;
#----------------------------------------------------------
sub help{
    print "Usage: rename [-h] perlexpr files

\"rename\" provides the filename in \$_ to perlexpr and 
renames according to the new value of \$_ modified by perlexpr.

You can use the special variable \$date to get the current date.

EXAMPLE: 
   -Lower case all *.TXT files: rename \'tr/A-Z/a-z/\' *.TXT
   -Change ending .HTM to .html: rename \'s/\\.htm\$/.html/i\' *.HTM
   -add a date at the beginning: rename \'s/^/\$date/\' *
\n";
    exit;
}
#----------------------------------------------------------
__END__
.TH RENAME 1 "July 30, 1990"
.AT 3
.SH NAME
rename \- renames multiple files
.SH SYNOPSIS
.B rename [-ih] perlexpr files
.SH DESCRIPTION
.I Rename
renames the filenames supplied according to the rule specified as the
first argument.
The argument is a Perl expression which is expected to modify the $_
string in Perl for at least some of the filenames specified.
If a given filename is not modified by the expression, it will not be
renamed.
.PP
.PP
For example, to rename all files matching *.bak to strip the extension,
you might say
.nf

	rename 's/\e.bak$//' *.bak

.fi
To translate uppercase names to lower, you'd use
.nf

	rename 'y/A-Z/a-z/' *

.fi
To do the same thing but leave Makefiles unharmed:
.nf

	rename 'y/A-Z/a-z/ unless /^Make/' *

.fi
To rename all the *.f files to *.BAD, you'd use
.nf

	rename 's/\e.f$/.BAD/' *.f

.SH ENVIRONMENT
.fi
No environment variables are used.
.SH AUTHOR
Larry Wall
.SH "SEE ALSO"
mv(1)
.br
perl(1)
.SH DIAGNOSTICS
If you give an invalid Perl expression you'll get a syntax error.
.SH BUGS
.ex