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