Re: GNATCOLL-Mmap example

[Stephen Leake <stephen_leake@stephe-leake.org>]

On Saturday, January 25, 2020 at 1:52:45 PM UTC-8, Bob Goddard wrote:
> Does anyone have a small GNATCOLL-Mmap example that I can use on Linux. Just can't see what to do and the "example" in the source  just doesn't work.

The full code for my usage is complex. Distilling it down, it becomes something like:

declare
   use GNATCOLL.Mmap;
   File : Mapped_File := Open_Read (file_name);
   Region : Mapped_Region := Read (File);
   Buffer : Str_Access := Data (region);
begin
  --  use Buffer as a string, but there are no bounds, so be careful.
end;

> I need to map the RPi's GPIO memory addresses so that I can do what I need to do.

I doubt Mmap is what you want; that is for mapping disk files to memory. To treat a memory address as a string, just use unchecked_conversion to gnatcoll.mmap.str_access, or something similar (remember a real String has bounds, but this doesn't).

--  Stephe