#!/usr/bin/perl -w
# https://lists.torproject.org/pipermail/tor-talk/2006-June/010486.html

use strict;

# Script to monitor the amount of FDs used by
# the Tor process (var/run/tor/tor.pid)

if ($ARGV[0] and $ARGV[0] =~ /^\s*config\s*$/i)
{
        print "graph_title Open file descriptors for Tor\n";
        print "graph_args --base 1000 -l 0\n";
        print "graph_vlabel open FDs\n";
        print "graph_category Tor\n";
        print "count.label TorFDs\n";
        exit 0;
}

my $pidfile = "/var/run/tor/tor.pid";
my $pid = '';
if (-e $pidfile) {
  open (PID, $pidfile) or exit 1;
  $pid = <PID>;
  close PID;
} else {
  $pid = `pidof tor`;
}
chomp $pid;

$pid =~ /^[0-9]+$/ or exit 1;

opendir (FDS, "/proc/$pid/fd") or exit 1;
my @fds = readdir(FDS);
closedir FDS;

my $count = scalar @fds - 2;

print "count.value $count\n";