System calls - GNAT library vs. direct bindings

[Maciej Sobczak <see.my.homepage@gmail.com>]

Hi,

I would like to now your opinion about the two options in the subject.

Let's suppose that the problem is a network-aware application on the
POSIX system. Ada doesn't know about network per RM, so we have to
look around for libraries.
One option is to use the GNAT library that has some package for
sockets.
Another is to write thin wrappers that bind directly to relevant
system calls (socket, connect, read, write, close, bind, listen,
accept, select - that's it for the basic stuff).

1. The advantage of using GNAT library is portability across various
systems that are targeted by GNAT. (I assume that the GNAT library is
available outside of POSIX - if not, please correct me.)

2. The advantage of writing custom thin wrappers is portability across
various compilers that target POSIX platforms.

The first is not really important for me, I will probably use only
POSIX systems.
The seconds is not important neither, I will probably use only GNAT.

In other words - the focus for evaluation should go elsewhere.
Performance? Maintainability? Some other factors?

Thank you for your feedback.

--
Maciej Sobczak
http://www.msobczak.com/