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From: Florian Weimer <fw@deneb.enyo.de>
Newsgroups: comp.lang.ada
Subject: Re: The "black magic" of ioctl
Date: Sat, 23 Oct 2010 22:26:51 +0200
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Date: 2010-10-23T22:26:51+02:00
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* Francesco Piraneo Giuliano:

> But my application still need to be written and has to run under linux
> so to collect some data about linux' framebuffer I have to use ioctl;
> the only solution is to write all low level interfacing (open the
> device, get informations about, map it into memory) in C then write
> the upper level in Ada?

ioctl is a varargs function.  You cannot call C varargs functions
directly from Ada.  You need to write a small wrapper with a fixed
number of arguments.

In addition, the ioctl constants are often difficult to extract from
the header files.  The best way to get them seems to be a small C
program which just prints them.

So writing some C code is unavoidable here.