#!/usr/bin/perl -w

use strict;

my $dir = shift;
$dir = $ENV{'PWD'} . '/' . $dir unless $dir =~ m#^/#;
$dir =~ s#([^/]*)$##;
my $trailing = $1;
$trailing = '' if $trailing eq '.' || !-d "$dir$trailing";
$trailing .= '/' if $trailing ne '';

open(IN, '/proc/mounts') or die $!;
while (<IN>) {
    $_ = (split)[1];
    next unless s#^\Q$dir$trailing\E##o && $_ ne '';
    print "/$trailing$_\n";
}
close IN;