HISTORY:
2.4.0:
- added ability to specify stdin for Session::Bash and Session::Sh
sh = Session::new
sh.execute 'cat', :stdin => io
sh.execute 'cat', :stdin => string
sh.execute 'cat', :stdin => stringio
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 classes built upon Open3::popen3 for driving
external progams via pipes. It offers a significant abstraction over
Open3::popen in that the stdout/stderr of each command sent can be deliniated:
open3:
i.o,e = Open3::popen3 '/bin/sh'
i.puts 'ls'
i.puts 'echo 42'
now, how to determine the boundry between the output from 'ls' and 'echo'?
the only (simple) way is start a process for each command
i.o,e = Open3::popen3 '/bin/sh'
i.puts 'ls'
i.close
stdout, stderr = o.read, e.read
i.o,e = Open3::popen3 '/bin/sh'
i.puts 'echo 42'
i.close
stdout, stderr = o.read, e.read
session:
sh = Session::new
stdout, stderr = sh.execute 'ls'
stdout, stderr = sh.execute 'echo 42'
Both stderr and stdout can be redirected, and the exit_status of each command
is made available:
bash = Session::Bash.new
stdout, stderr = StringIO::new, StringIO::new
bash.execute 'ls', :stdout => stdout, :stderr => stderr
# bash.execute 'ls', 1 => stdout, 2 => stderr # same thing
# bash.execute 'ls', :o => stdout, :e => stderr # same thing
exit_status = bash.exit_status
A block form can be used to specify a callback to be invoked whenever output
has become availible:
bash = Session::Bash.new
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 commands spawned 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
enjoy.
-a