[Haskell-cafe] [ANNOUNCE] Bindings for libguestfs

[Richard W.M. Jones]

On Tue, May 12, 2009 at 08:18:08AM -0700, Don Stewart wrote:
> rjones:
> > I added some partial bindings for libguestfs[1] here:
> > 
> > http://git.et.redhat.com/?p=libguestfs.git;a=blob;f=haskell/Guestfs.hs;hb=HEAD
> > 
> > Some very simple example programs which use these bindings:
> > 
> > http://git.et.redhat.com/?p=libguestfs.git;a=tree;f=haskell;hb=HEAD
> > 
> > Any comments welcome.  My Haskell skills are pretty terrible, so I'm
> > sure there are many ways these can be improved.
> > 
> > If someone wants to look at binding the rest of the API, then please
> > send me some patches.  (Note that the Guestfs.hs file is automatically
> > generated).
> 
> Very cool. Are you likely to upload to hackage?

I think it should be a bit more complete before uploading it.  It only
covers about half the interface.

> > BTW, I found the documentation on writing FFIs very contradictory and
> > incomplete.  For example, I was completely defeated trying to find
> > ways to do simple stuff like passing in integers or returning
> > booleans.  *Potentially* Haskell's FFI seems like it might be one of
> > the best out of the languages I've used so far, but it needs way more
> > documentation and examples.
> 
> Perhaps read the FFI chapter of RWH (online?)
>
> What resources were you using to grok the FFI?

Well, Real World Haskell was one of the resources:

http://book.realworldhaskell.org/read/interfacing-with-c-the-ffi.html

(And it's fine, one of the better resources as an introduction.  But
not thorough enough to cover the booleans / returning complex structs
problems I had).

The others, as I remember it, were:

http://www.haskell.org/haskellwiki/FFI_Introduction
http://www.haskell.org/haskellwiki/FFICookBook

(Made me think it was simple, but doesn't really cover much once I got
down to the details)

http://www.cse.unsw.edu.au/~chak/haskell/ffi/

& the documentation for 'Foreign' etc in the Haddock-generated library
docs.

Rich.

-- 
Richard Jones, Emerging Technologies, Red Hat  http://et.redhat.com/~rjones
virt-df lists disk usage of guests without needing to install any
software inside the virtual machine.  Supports Linux and Windows.
http://et.redhat.com/~rjones/virt-df/