From: Tobias Reif <tobiasreif@...>
Date: 2003-09-05T00:25:21+09:00
Subject: backtick calls on Windows (9*)

Hi

I'm disappointed to see that stuff like www.ruby-talk.org/9739 and 
www.ruby-talk.org/10006 still is required with the latest version of 
Ruby on Windows.
Over the years there have been many long threads already, so in order to 
not increase the list volume too much, this is a one-post wish for (one 
aspect of) better Windows support. (Not a fifty-message thread about how 
lame Windows is :)

Here's an illustration of the problem:
(Ruby hackers (implementers) please feel free to contact me offlist for 
further details if required)

# latest PragProg installer
# ruby 1.8.0 (2003-08-04) [i386-mswin32]

tidy_version_command = 'tidy -v'
puts `#{tidy_version_command}`
# backticks:6:in ``': No such file or directory -
# tidy -v (Errno::ENOENT)

xmllint_version_command = 'xmllint --version'
puts `#{xmllint_version_command}`
# backticks:11:in ``': No such file or directory
# - xmllint --version (Errno::ENOENT)

$:<<'[/path/to]/ruby/shared/' # path string changed in post
require 'cross_os_calls.rb'

tidy_version_command = 'tidy -v'
puts `#{tidy_version_command}`
# HTML Tidy for Windows released on 1st February 2003

xmllint_version_command = 'xmllint --version'
puts `#{xmllint_version_command}`
#[...]\XMLLINT.EXE: using libxml version 20510 [...]


... where cross_os_calls.rb goes something like this:


require 'rbconfig'

alias oldBacktick `

def `(command)
   if Config::CONFIG["arch"] =~ /win/
     require 'Win32API'
     popen = Win32API.new("crtdll", "_popen", ['P','P'], 'L')
     pclose = Win32API.new("crtdll", "_pclose", ['L'], 'L')
     fread = Win32API.new("crtdll", "fread", ['P','L','L','L'], 'L')
     feof = Win32API.new("crtdll", "feof", ['L'], 'L')
     saved_stdout = $stdout.clone
     psBuffer = " " * 128
     rBuffer = ""
     f = popen.Call(command,"r")
     while feof.Call( f )==0
       l = fread.Call( psBuffer,1,128,f )
       rBuffer += psBuffer[0..l]
     end
     pclose.Call f
     $stdout.reopen(saved_stdout)
     rBuffer
   else
     oldBacktick command
   end
end

It might be a good idea to include something like the above in Ruby.

Tobi

-- 
http://www.pinkjuice.com/