[Haskell-cafe] HDBC-postgresql and safe/unsafe FFI calls

David Powell david at drp.id.au
Thu Sep 2 01:00:08 EDT 2010


Thanks Jason, I think I had read that - I quite enjoy Edward's posts.
Re-reading, seems to confirm what I thought, most (all?) of the FFI calls in
HDBC-postgresql should be changed to "safe".

-- David

On Thu, Sep 2, 2010 at 2:47 PM, Jason Dagit <dagit at codersbase.com> wrote:

> On Wed, Sep 1, 2010 at 7:40 PM, David Powell <david at drp.id.au> wrote:
> > Greetings,
> >
> > I'm having an issue with the HDBC-postgresql package that requires me to
> > manually patch it before installation for most of my use cases.
> >
> > All the FFI calls in this package are marked "unsafe".  Unfortunately,
> this
> > means that whenever I issue a slow sql query, all other processing stops.
> > In most places that I want to use this module, I've had to manually patch
> it
> > to at least mark the PQexec and PQexecParams calls as "safe".
> >
> > Is there any reason these calls should not be marked as "safe"?  I
> > understand that there a little extra runtime overhead with this, but I'd
> > have thought that negligible given all the other processing that goes on
> > with these particular calls under the hood.
>
> Have you read this?
> http://blog.ezyang.com/2010/07/safety-first-ffi-and-threading/
>
> Perhaps it answers your questions?
>
> Jason
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://www.haskell.org/pipermail/haskell-cafe/attachments/20100901/a9fceef8/attachment.html


More information about the Haskell-Cafe mailing list