Re: Gnat 2013 is out!

[Dennis Lee Bieber <wlfraed@ix.netcom.com>]

On Tue, 27 Aug 2013 16:05:20 -0400, wilson <winslole@udayton.edu> declaimed
the following:

>On Tue, 27 Aug 2013 10:08:34 -0400, Yannick Duchêne (Hibou57)  
><yannick_duchene@yahoo.fr> wrote:
>
>> I personally did not used a debugger since Borland Turbo Pascal. I first  
>> missed it (at that time GDB for C programs had issues on Windows 3.1),  
>> but quickly figured a debugger only show you one particular path in your  
>> logic, and above all, consume a lot of your time to just follow this  
>> path, a lot of time which is not used to understand the properties of  
>> the whole.
>>
	<snip>

>>
>> When something really drives me crazy, I just add a “sentinel” which  
>> prints out some information (just requires an “with Ada.Text_IO” and a  
>> line added somewhere to print an “Element'Image”) I fill to not track  
>> correctly, to help me a bit. Then, back to global understanding as soon  
>> as possible.
>>
	<snip>

>> Another issue, is that a program is not always running in a debugger,  
>> and so what when something went wrong while it was not running in a  
>> debugger and you don't have a complete and exact snapshot of the  
>> program's state when it get wrong? Here, a logger surely help more than  
>> a debugger, as it may be active all the time (most platform provides an  
>> API to help automatically manage logs and avoid these logs to fill all  
>> of your storage space).
>
>Thank you for saying something I have felt for years.  I always felt odd  
>man out for this approach and it is good to have someone else say the same  
>thing.

	I've only made significant use of one debugger -- the one on DEC VMS.
The VMS debugger is basically one big exception handler with ties to
embedded debug information (mainly tags for source file/version/line
number, and symbol table).

	The only other debugger I even touched was the one in LS-DOS (TRS-80).
And that was mainly because the "advanced" debugger mode included commands
to do raw sector I/O on the floppy drives (including command to write the
special directory block disk header). Why? I received an O/S update disk
that had a bad sector. With some work I was able to determine which file
was bad. I then compared the sectors of my working O/S disk to the bad one,
WRT that file. I determined the sectors before and after the bad one had
one or two bytes different -- namely, the bytes that changed the default
layout for the directory display. So I used the debugger to duplicate all
of the update disk except for the bad sector, which I then copied over from
my working disk.

	The new disk worked well, and I sent the bad disk back to the maker
with a description of the problem. (I believe the update was to handle
larger date ranges -- the original LS-DOS/TRS-DOS used a 3-bit YEAR,
essentially 1977 [78?] to 1984 [85?]; the update removed user-passwords
from directory entries to expand the date... Y2K had nothing on the TRS-80
<G> Files had owner and user passwords, but how many people are going to
use owner password to set a file read-only, AND then require a user
password just to read the file...)
-- 
	Wulfraed                 Dennis Lee Bieber         AF6VN
    wlfraed@ix.netcom.com    HTTP://wlfraed.home.netcom.com/