[GRASS-dev] [grass-code I][478] tcl/tk gui startup screen launches grass even when 'Exit' is pushed

[Paul Kelly]

Hello all
(sorry for delayed response on this; been travelling a lot and only have 
time to "dip in" to mailing list discussions at the minute...)

On Thu, 20 Sep 2007, Moritz Lennert wrote:

> On 20/09/07 11:25, Maciej Sieczka wrote:
>> Hi
>> 
>> Ma-ris Narti?s has submitted a patch into GForge [1]. I'm copying his
>> message below. Please somebody review and submit.
>
> Just tested and it seems to work. Committed.

I think it's a good idea to change the behaviour here, but I feel the 
patch doesn't really address the problem: rather it adds more code to work 
around it. In particular, clicking exit in the gis_set.tcl Window won't 
work with init.bat (Windows) now, as it used the exit code of 1 to 
indicate exit (whereas the patch makes an exit code of 2 now indicate 
exit). I notice also the patch makes the exit code of the Python version 
of gis_set.tcl be interpreted differently - has anybody checked what 
effect this will have?

The problem is the historical behaviour that an error in gis_set.tcl (e.g. 
the wrong version of Tcl/Tk) caused it to drop out from attempting the GUI 
startup but go ahead and start an interactive GRASS shell. When I made 
a few changes to the return codes from gis_set.tcl I deliberately avoided 
tackling this because I wasn't sure what was the best solution. But on 
thinking about it more, I think dropping to an interactive shell is the 
wrong approach. It should print a warning/error message and then exit, and 
if the user wants to start in text-based mode instead they can use the 
-text switch next time round.

init.bat assumes a return code of 1 means exit. I vaguely intended the 
same interpretation for Init.sh, and to remove the facility to drop to an 
interactive shell when there was an error in gis_set.tcl, but I didn't 
implement this nor tell anybody about my plans: my fault ;)

I think it would simplify things if we made Init.sh always exit when a 
non-zero exit code is returned from gis_set.tcl- any other thoughts? (I 
should probably update init.bat too so it goes ahead when 0 is returned, 
rather than exiting when 1 is returned).

Paul