title: Install Ruby Curb gem in windows XP
body: <p>I'm trying to do file uploads with ruby 1.8 and it seems like there are no good out-of-the-box solutions. They all seem to need some 3rd party patch or fork of a project to work. I would use mechanize but I actually need to interface with an xml api and mechanize seems to be made specifically for dealing directly with webpages. I've tried RestClient but it doesn't have that functionality for multipart forms out of the box, you have to use a fork of the project to get it to work. Similar situations seem to exist for Net:HTTP
  I'm thinking curb would be the way to go since I may want to use multicurl anyways for some other things I plan to do. However, on my windows machine I can't seem to install the curb gem. gem install curb gives an error saying I need to specify where the curl library lives.. I've tried passing options to extconf but no luck so far.
  Here is the output of gem install curb without any options</p>
  
  <pre><code>C:\ruby\lib\ruby\gems\1.8\gems\curb-0.5.4.0&gt;gem install curb
  Building native extensions.  This could take a while...
  ERROR:  Error installing curb:
          ERROR: Failed to build gem native extension.
  
  C:/ruby/bin/ruby.exe extconf.rb
  checking for curl-config... no
  checking for main() in curl.lib... no
  *** extconf.rb failed ***
  Could not create Makefile due to some reason, probably lack of
  necessary libraries and/or headers.  Check the mkmf.log file for more
  details.  You may need configuration options.
  
  Provided configuration options:
          --with-opt-dir
          --without-opt-dir
          --with-opt-include
          --without-opt-include=${opt-dir}/include
          --with-opt-lib
          --without-opt-lib=${opt-dir}/lib
          --with-make-prog
          --srcdir=.
          --curdir
          --ruby=C:/ruby/bin/ruby
          --with-curl-dir
          --without-curl-dir
          --with-curl-include
          --without-curl-include=${curl-dir}/include
          --with-curl-lib
          --without-curl-lib=${curl-dir}/lib
          --with-curllib
          --without-curllib
  extconf.rb:12:   Can't find libcurl or curl/curl.h (RuntimeError)
  
    Try passing --with-curl-dir or --with-curl-lib and --with-curl-include
    options to extconf.
  
  
  Gem files will remain installed in C:/ruby/lib/ruby/gems/1.8/gems/curb-0.5.4.0 for inspection.
  Results logged to C:/ruby/lib/ruby/gems/1.8/gems/curb-0.5.4.0/ext/gem_make.out
  </code></pre>
  
  <p>Any ideas how I can get this to work?</p>