[GRASS-dev] making grass modules less verbose

[Michael Barton]

Jachym and others,

I want to put my support behind this effort. It helps address an issue I've
run into wrapping GRASS in a GUI--and whined to the list periodically.
Thanks very much.

Michael
__________________________________________
Michael Barton, Professor of Anthropology
School of Human Evolution & Social Change
Center for Social Dynamics and Complexity
Arizona State University

phone: 480-965-6213
fax: 480-965-7671
www: http://www.public.asu.edu/~cmbarton


> From: Jachym Cepicky <jachym.cepicky at centrum.cz>
> Date: Wed, 20 Sep 2006 13:18:47 +0200
> To: Paul Kelly <paul-grass at stjohnspoint.co.uk>
> Cc: <grass-dev at grass.itc.it>
> Subject: Re: [GRASS-dev] making grass modules less verbose
> 
> hallo Paul,
> 
> On Wed, Sep 20, 2006 at 11:52:13AM +0100, Paul Kelly wrote:
>> Hello Jachym
>> In order to keep module output as consistent as possible, I feel it might
>> be better to implement this as a "quiet" flag rather than a verbose flag?
>> I.e. by default output continues as normal but if, as you say the modules
>> need to be used in something like an emebedded system with minimal output
>> then the quiet flag could be specified.
> 
> http://www.faqs.org/docs/artu/ch11s09.html
> 
> I'm not UNIX coder, but I think, I can agree with most of the statemets
> listed in this chapter of Art Of Unix Programing:
> 
> 1) If your CLI program emits status messages to standard output, then
> programs that try to interpret that output will be put to the trouble of
> interpreting or discarding those messages (even if nothing went wrong!).
> 
> *Better to send only real errors to standard error and not to emit
> unrequested data at all.*
> 
> g.remove (?)
> 
> 2) The user's vertical screen space is precious.
> 
> v.in.ascii (?)
> 
> 3) Junk messages are a careless waste of the human user's bandwidth.
> 
> g.remove
> 
> 4) In general, it's bad style to tell the user things he already knows.
> 
> 5) be chatty only about things that deviate from what's normally
> expected. 
> 
> G_fatal_error() will always be printed
> 
> This was the reasons, i was thinking about, when adding --verbose
> and not --quiet flag. Most of the people do not actually care, that
> some module is "opening raster files". The work can be done in
> background. --verbose could be first step of debuging info. Because of
> the user wants to check the progress of the program, i'm suggesting the
> idea of log file, which would be removed after grass session is done.
> 
> Anyway, if most of the developers would prefere --quite, it is no
> problem to implement this and also to change GRASS_VERBOSE to
> GRASS_QUITE.
> 
>> 
>> I was thinking also it would be a good test for which modules write
>> directly to stderr and which should possibly be changed to use
>> G_message(), if you set the quiet flag before running them. Although
>> G_message() doesn't offer as much flexibility as printing to stderr,
>> e.g. no backspace or bell.
>> 
>> Paul
>> 
> 
> How difficult would it be to make G_message to be able to print
> backspaces or bells?
> 
> Jachym
> 
>> On Wed, 20 Sep 2006, Jachym Cepicky wrote:
>> 
>>> On Wed, Sep 20, 2006 at 09:37:36AM +0200, Sören Gebbert wrote:
>>>> Hi,
>>>> i think this is a nice idea.
>>>> Some modules are very verbose and with this approach a general
>>>> way is provided to handle this verbosity.
>>>> 
>>>> Best regards
>>>> Soeren
>>>> 
>>> 
>>> I prepared new patch (for current cvs version) which makes all modules
>>> be able to use --verbose flag or to set GRASS_VERBOSE env. variable.
>>> 
>>> G_message, G_warning and G_percent are now able to handle according to
>>> the user needs.
>>> 
>>> Could anybody test this?
>>> 
>>> If this works well and nobody has any objection, I would implement the log
>>> file idea.
>>> 
>>> The hard part will be go throu all modules and replace (f)printf for
>>> G_message(), but I could take care on this. Another thing: parts of g.*
>>> and v.* modules do not use G_message at all.
>>> 
>>> Jachym
>>> 
>>> -- 
>>> Jachym Cepicky
>>> e-mail: jachym.cepicky at centrum.cz
>>> URL: http://les-ejk.cz
>>> GPG: http://les-ejk.cz/gnupg_public_key/jachym_cepicky-gpg_public_key.asc
>>> -----------------------------------------
>>> OFFICE:
>>> GDF-Hannover
>>> Mengendamm 16d
>>> 30177 Hannover
>>> Germany
>>> e-mail: cepicky at gdf-hannover.de
>>> URL:    http://gdf-hannover.de
>>> Tel.:   +49 511-39088507
>>> 
> 
> 
> -- 
> Jachym Cepicky
> e-mail: jachym.cepicky at centrum.cz
> URL: http://les-ejk.cz
> GPG: http://les-ejk.cz/gnupg_public_key/jachym_cepicky-gpg_public_key.asc
> -----------------------------------------
> OFFICE:          
> GDF-Hannover
> Mengendamm 16d
> 30177 Hannover
> Germany
> e-mail: cepicky at gdf-hannover.de
> URL:    http://gdf-hannover.de
> Tel.:   +49 511-39088507