== Description
  A collection of classes that provide different ways to ping computers.

== Prerequisites
  * ffi
  * win32-security (MS Windows only)
  * fakeweb (test only)
  * test-unit (test only)

  JRuby users should use JRuby 1.6.7 or later.

== Installation
  gem install net-ping

== Notes
  Please read the documentation under the 'doc' directory. Especially pay
  attention to the documentation pertaining to ECONNREFUSED and TCP pings.

  Also note the documentation regarding down hosts.

  You do not need win32-open3 with Ruby 1.9.x. The open3 library that ships
  as part of the Ruby standard library should work.

== How to require net-ping
  You can do either this:

  require 'net/ping'

  In which case you will get Net::Ping and all of its subclasses. Or,
  you can load individual subclasses like this:

  require 'net/ping/tcp'

  The former has the advantage of being easier to remember and all inclusive,
  not to mention backwards compatible. The latter has the advantage of
  reducing your memory footprint.

== Known Issues

  **UDP**
  Older versions of Ruby 1.9.x may not work with UDP pings.

  Older versions of JRuby will return false positives in UDP pings
  because of an incorrect error class being raised. See JRuby-4896.

  Jruby hangs if UDP ping doesn't receive a return packet. See JRuby-6974.

  **External**
  JRuby 1.6.7 or later is required for external pings because of a bug
  in earlier versions with open3 and stream handling.

  **ICMP**
  ICMP pings are not supported by JRuby or Rubinus. See JRuby-5897
  ICMP pings are not thread safe. See https://www.ruby-forum.com/topic/146116.
  Patches welcome.

  **TCP**
  TCP pings are not supported under JRuby: they fail with Errno::ECONNREFUSED.

== License
  Artistic 2.0

== Contributions
  Although this library is free, please consider having your company
  setup a gittip if used by your company professionally.

  http://www.gittip.com/djberg96/

== More documentation
  If you installed this library via Rubygems, you can view the inline
  documentation via ri or fire up 'gem server', and point your browser at
  http://localhost:8808.

== Author
  Daniel J. Berger