Re: [Chicken-users] Getting C file handle from port?

[Peter Bex]

On Sat, Mar 20, 2010 at 10:58:54AM -0300, Jeronimo Pellegrini wrote:
> Hello,
> 
> Suppose I have an open port:
> 
> (let ((in (open-input-file "whatever")))
>   ...
>   (let ((x (read in)))
>     ...))
> 
> I'd like to switch from using Chicken's read implementation to
> something I'd write in C (using the FFI). But I didn't find in
> the documentation anything that would allow me to turn a port
> into a C file handle.

I don't know about file *handles* (ie of type FILE *), but you can
obtain the descriptor using port->fileno in the POSIX unit:
http://chicken.wiki.br/man/4/Unit posix#port-fileno

You might then use the POSIX function fdopen(3) to convert the
descriptor into a FILE *.

> Is it possible at all?

It's always possible!

Cheers,
Peter
-- 
http://sjamaan.ath.cx
--
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