From: Ollivier Robert <roberto@...>
Date: 2009-01-19T20:23:44+09:00
Subject: Re: [FFI] how to bind to a function with variable number of args

In article <AE36BD1B-11A2-4135-AB0E-33E531C2DADA@honk-honk.com>,
Luc Heinrich  <luc@honk-honk.com> wrote:
>This would be defined like this:

The following does not work:
-----
module LibC
  extend FFI::Library
  
  attach_function :setproctitle, [:string, :varargs], :void
end

LibC.setproctitle("Ruby: executing %s", [:string, $0])
-----

Same error:
/opt/local/lib/ruby/gems/1.8/gems/ffi-0.2.0/lib/ffi/library.rb:65:in
`attach_function': Function 'setproctitle' not found in [[current process]]
(FFI::NotFoundError) from proc.rb:12

(OS X, 10.5.6, Ruby from MacPorts)

UPDATE: setproctitle may not be available in OS X. Retrying on FreeBSD leads
to this:

/usr/local/lib/ruby/gems/1.8/gems/ffi-0.2.0/lib/ffi/types.rb:18:in `find_type': Unable to resolve type 'stringproc.rb' (FFI::TypeError)
        from /usr/local/lib/ruby/gems/1.8/gems/ffi-0.2.0/lib/ffi/variadic.rb:23:in `call'
        from (eval):3:in `setproctitle'
        from proc.rb:15

-- 
Ollivier ROBERT -=- EEC/RIF/SEU -=-
Systems Engineering Unit