From: Eric Hodel <drbrain@...7.net>
Date: 2005-07-18T05:11:30+09:00
Subject: Re: Cheapest ping possible

On 17 Jul 2005, at 07:20, Daniel Berger wrote:

> Matthew Margolis wrote:
>
>> I know about ruby ping
>> (http://www.ruby-doc.org/stdlib/libdoc/ping/rdoc/index.html).  Has
>> anyone used this library for a lot of concurrent pings?  Are there  
>> any
>> better solutions out there for what I need?
>
> I use net-ping, available on the RAA.  I use that because, well, I
> wrote it. :)
>
> Yes, threads are probably the way to go:
>
> require "net/ping"
> include Net
>
> threads = []

threads = ThreadGroup.new

> hosts.each{ |host_to_ping|
>    threads << Thread.new(host_to_ping){ |host|
    threads.add Thread.new(host_to_ping){ |host|
>       ping_obj = PingTCP.new(host) # or UDP, or whatever you prefer
>       unless ping_obj.ping?
>          # Failed to ping 'host'
>       end
>    }
> }
>
> threads.each{ |t| t.join }
threads.list.each { |t| t.join }

A ThreadGroup doesn't hang on to dead threads, so if a thread  
finishes it will be garbage collected.

-- 
Eric Hodel - drbrain@segment7.net - http://segment7.net
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