From: nobu.nokada@...
Date: 2004-11-15T10:21:13+09:00
Subject: Re: Win32, file descriptors and rb_io_check_writable()

Hi,

At Sat, 13 Nov 2004 08:13:26 +0900,
Daniel Berger wrote in [ruby-talk:120101]:
> But, I cannot write to the filehandle:
> 
> fh = File.nopen("C:\\somefile")
> fh.puts "Hello"
> 
> test.rb:13:in `write': not opened for writing (IOError)
>         from test.rb:13:in `puts'
>         from test.rb:13
> 
> That error appears to be coming from the rb_io_check_writable()
> function, which in turn is checking the mode of the OpenFile struct
> defined in rubyio.h.
> 
> How do I deal with this?  Am I doing something wrong?  Or would it
> take a modification of io.c for this to work?  If so, what should be
> done?

File#initialize accepts the mode in Fixnum.

>    // Convert HANDLE to file descriptor
>    args[0] = UINT2NUM(_open_osfhandle((long)h,O_RDWR));
     switch (dwAccess & (GENERIC_READ|GENERIC_WRITE)) {
       case 0:
         args[1] = INT2FIX(0);
         break;
       case GENERIC_READ:
         args[1] = INT2FIX(O_RDONLY);
         break;
       case GENERIC_WRITE:
         args[1] = INT2FIX(O_WRONLY);
         break;
       default:
         args[1] = INT2FIX(O_RDWR);
         break;
     }
>    
>    // Return a bonafide File object, based on the file descriptor
     return rb_class_new_instance(2,args,klass);
> }

-- 
Nobu Nakada