Shell timeout test for PTY exits

example.rb

require 'pty'

#
# To add to results:
# 
#   echo "# OS" >> results.txt
#   ruby example.rb | tee -a results.txt
#

shells = ARGV
shells = %w{/bin/bash /bin/csh /bin/ksh /bin/zsh} if shells.empty? 
timeout = 3 

$stderr.puts "0. shell"
$stderr.puts "1. PTY - select on slave"
$stderr.puts "2. PTY - select on slave, clearing the slave after kill"
$stderr.puts "3. PTY - select on slave, closing streams after kill"
$stderr.puts "*  timeout waiting on slave"

puts "# #{`ruby --version`}"
shells.each do |shell|
  printf "#{shell}\t"
  
  `which '#{shell}'`
  unless $?.exitstatus == 0
    printf "%8s\t%8s\t%8s\n" % %w{- - -}
    next
  end

  # 1. PTY - select on slave
  PTY.spawn(shell) do |slave, master, pid|
    unless IO.select([slave],nil,nil,timeout)
      printf "* "
    end

    start = Time.now
    Process.kill(9, pid)
    Process.wait(pid) rescue PTY::ChildExited
    printf "%.6f\t", Time.now - start
  end

  # 2. PTY - select on slave, clearing the slave after kill
  PTY.spawn(shell) do |slave, master, pid|
    unless IO.select([slave],nil,nil,timeout)
      printf "* "
    end

    start = Time.now
    Process.kill(9, pid)

    slave.read rescue Errno::EIO

    Process.wait(pid) rescue PTY::ChildExited
    printf "%.6f\t", Time.now - start
  end

  # 3. PTY - select on slave, closing streams after kill
  PTY.spawn(shell) do |slave, master, pid|
    unless IO.select([slave],nil,nil,timeout)
      printf "* "
    end

    start = Time.now
    Process.kill(9, pid)

    master.close
    slave.close

    Process.wait(pid) rescue PTY::ChildExited
    printf "%.6f\n", Time.now - start
  end
end

results.txt

# OS X 10.5.8
# ruby 1.8.7 (2011-02-18 patchlevel 334) [i686-darwin9.8.0]
/bin/bash	0.600294	0.000258	0.057034
/bin/csh	0.600335	0.000334	0.055263
/bin/ksh	0.600467	0.000260	0.060063
/bin/zsh	0.600302	0.000279	0.053442
# OS X 10.6.8
# ruby 1.8.6 (2010-02-05 patchlevel 399) [i686-darwin10.4.0]
/bin/bash	0.601312	0.000303	0.056619
/bin/csh	0.601657	0.000363	0.050967
/bin/ksh	0.602031	0.000352	0.057968
/bin/zsh	0.601496	0.000373	0.051002
# Ubuntu 11.04
# ruby 1.9.2p290 (2011-07-09 revision 32553) [i686-linux]
/bin/bash	0.001165	0.001289	0.001075
/bin/csh	0.100429	0.100702	0.000523
/bin/ksh	0.001285	0.001559	0.001251
/bin/zsh	0.001535	0.001573	0.001559
# Ubuntu 11.10
# ruby 1.8.7 (2011-06-30 patchlevel 352) [i686-linux]
/bin/bash	0.012751	0.030525	0.036334
/bin/csh	0.055288	0.057541	0.047337
/bin/ksh	0.059810	0.060154	0.042831
/bin/zsh	0.037786	0.001283	0.049365
# SLES 10
# ruby 1.8.6 (2010-02-05 patchlevel 399) [i686-linux]
/bin/bash	0.039185	0.001369	0.026253
/bin/csh	0.060401	0.038210	0.013586
/bin/ksh	0.032744	0.001268	0.061503
/bin/zsh	0.043043	0.009338	0.021305