check_proc_count

#!/usr/bin/env bash
#
# Count the number of running processes
#
# This is not directly an indicator of a problem,
# but instead is usually a symptom of a misbehaving
# program
#
# Author: Dave Eddy <dave@voxer.com>
# Date: 11/21/12
# License: MIT

warning=250
critical=400
perfdata=true
while getopts 'nw:c:' option; do
	case "$option" in
		n) perfdata=false;;
		w) warning=$OPTARG;;
		c) critical=$OPTARG;;
	esac
done

count=$(ls -U1 /proc | wc -l)

if [[ -z $count ]]; then
	echo 'unknown: could not count procs in /proc'
	exit 3
elif (( count >= critical )); then
	echo -n 'critical: '
	ret=2
elif (( count >= warning )); then
	echo -n 'warning: '
	ret=1
else
	echo -n 'ok: '
	ret=0
fi

echo -n "$count processes running"
$perfdata && echo "|proc_count=$count" || echo
exit "$ret"