Re: ISO/IEC 14519 - Ada POSIX binding

[Mark Lorenzen <mark.lorenzen@ofir.dk>]

Wesley Groleau <wesgroleau@despammed.com> writes:

> The POSIX binding I looked at had a single exception,
> POSIX_Error and then you were supposed to examine the
> errno variable.  Proctalgia, but it's the price you pay
> for interfacing to such a primitive system.  Rather than
> "roll-your-own" completely, I'd say use POSIX as a thin
> binding and provide a thick binding to wrap it in.

Yes! The POSIX binding is a (not so)simple binding to a low-level
interface and is therefore also pretty low-level. But it has a huge
advantage, namely that it is POSIX (read PORTABLE) - it is even
implemented for some RT OSes.

I would appreciate a high-level socket or general communication
package, but I think that it is important that the package is based on
the POSIX interface as the interface has a lot of other useful stuff
than just sockets. Imagine that we want to use asynchronous I/O on a
socket - POSIX support that. But async I/O often uses POSIX real-time
signals for event signalling and again it is provided by the POSIX
interface.

When using sockets for real applications, we often need to drag a
whole toolsbox into use f.x. select() or poll(), fcntl(), ioctl() and
so on.

The Ada POSIX Interface is modular, just as the C counterpart, so an
implementation need not implement the whole standard (message queues,
async I/O, co-existence with C threads, RT signals and so on...).

- Mark