Simple process monitor tool like `top` in ruby for linux.

procmon.rb

#!/usr/bin/ruby
require 'thread'
require 'logger'

$KCODE = "utf-8"

class ProcMon < Logger::Application
    def initialize()
          super('ProcMon') # Name of the application.
    end

    def run
        p = `ps aux`
        c = 0
        val = $0.gsub(/.*\//,"")
        while p =~ /ruby.*#{val}/o
            c = c + 1
            p = p.sub(/#{val}/o, "")
        end
	if c > 1
            @log.error("Duplex run")
	    exit
	end

	#loading list
	l = IO.read('/usr/local/etc/procmon.conf')
	mpl = []
	l.each {|prg|
	    prg = prg.sub(/\n$/,'')
	    next if prg == ''
	    if prg =~ /.*\/+?(.*)/
		name = $1
	    else
		name = prg
	    end
	    mp = {  'found' => false,
		    'fullname' => prg,
		    'name' => name
		}
	    mpl.push(mp)
	}
	
	while(true)
	    pl = `ps ax`
	    pl.each { |prc|
		next if prc !~ /^\s*(\d+)\s+\S+\s+\S+\s+[\d:]+\s+(.*)\s+$/
		name = $2
		mpl.each {|mp| 
		    if name =~ /#{mp['name']}/
			mp['found'] = true
			log(DEBUG, "The program #{mp['fullname']} has already run")
		    end
		}
	    }

	    mpl.each {|mp|
		unless mp['found']
		    log(INFO, "The #{mp['fullname']} program will be run")
		    pid = fork {`#{mp['fullname']} &`}
		    Process.detach(pid)
		    log(INFO, "Program has run")
		end
		mp['found'] = false
	    }

	    sleep 10
	end
    end
  end

status = ProcMon.new().start