use File::chdir;

print $CWD;

# now cd and show me a directory listing
{
   local(@CWD,$CWD);
   push @CWD,'subdir';
   print $CWD;
   
   print join("\n", glob '*');
}


# now we're back where we started.  We'll do a listing to show.
print $CWD;
print join("\n", glob '*');

##</code><code>##

use File::chdir;
my $wd = $CWD;

chdir('subdir');
# do some work.

$CWD = $wd; # return to saved dir.