From: "Ara.T.Howard" <Ara.T.Howard@...>
Date: 2004-10-06T01:44:52+09:00
Subject: [ANN] session-2.1.8


URLS: |

   http://raa.ruby-lang.org/project/session/
   http://www.codeforpeople.com/lib/ruby/session/


NAME: |

   Session
     ::Sh
     ::Bash
     ::Shell
     ::IDL

SYNOPSIS: |

   Session::* offers a set of class for driving external progams via pipes.  It
   offers a significant abstraction over Open3::popen since stdout/stderr can
   be processed individually for each command.  Additionally the exit_status of
   each command is made available.  eg.

     bash = Session::Bash.new
     stdout, stderr = bash.execute 'ls'

   or

     bash = Session::Bash.new
     stdout, stderr = StringIO.new, StringIO.new

     bash.execute 'ls', :stdout => stdout, :stderr => stderr
     exit_status = bash.exit_status

   or

     bash = Session::Bash.new
   #
   # output is passed to the block as it is produced
   #
     bash.execute( 'long_running_command.exe' ) do |out, err|
       logger << out if out
       elogger << err if err
     end

   Sessions are Thread safe (in the sense that they do not block on io
   operations) allowing command spawn from guis to update widgets with output
   while running in the background.

     button.configure 'action' => lambda do
       sh = Session::new
       sh.execute(cmd) do |o,e|
         out_widget.update o if o
         err_widget.update e if e
       end
     end

SAMPLES: |

   see samples/*


AUTHOR: |

   ara.t.howard@noaa.gov


HISTORY: |

   2.1.8:
     - greatly simplified read loop using two reader threads, one for stderr and
       one for stdout alongside a mutex to protect data.  this streamlined the code
       alot vs. the old select method including allowing removal of the linbuffer
       class.  the interface remains exactly as before however.
   2.1.7:
     - improved thread safe non-blocking read method
     - gemspec
   2.1.6:
     - wrapped send_command in a Thread (send async) so output processing can
       commend immeadiately.  this was o.k. before, but had strange behaviour when
       using popen3 from threads.  thanks to tanaka akira for this suggestion.
     - iff ENV['SESSION_USE_SPAWN'] is set Session uses Spawn::spawn instead of
       Open3::popen3.  also noted that spawn seems to be a bit faster.
     - added tests for threads.
     - run 'sh SESSION_USE_SPAWN=1 ruby test/session.rb' to test using spawn
     - added test for idl so it's test is not run if system doesn't have it, all
       that should be required for 'ruby test/session.rb' is should be sh'
     - removed sample/tcsh and note about Tcsh and Csh in README - stderr
       redirection/separation is flaky in those shells
   2.1.5:
     - added Session.use_spawn=, AbstractSession.use_spawn=, and an :use_session=>
       option to AbstractSession#initialize.  if any of them are set the code uses
       Spawn::spawn to create external processes instead of Open3::popen3.
       Spawn::spawn uses named pipes (fifos) for IPC instead of forking and pipes.
       the fork used in popen3 can cause strange behaviour with multi-threaded apps
       (like a tk app).  see source for details
   2.1.4:
     - added Thread.exclusive{} wrapper when io is read to works in multi
       threaded apps

enjoy.


-a
--
===============================================================================
| EMAIL   :: Ara [dot] T [dot] Howard [at] noaa [dot] gov
| PHONE   :: 303.497.6469
| A flower falls, even though we love it;
| and a weed grows, even though we do not love it. 
|   --Dogen
===============================================================================