[GRASS-dev] Re: [GRASS-SVN] r34913 - grass/branches/develbranch_6/general/g.gisenv

[Glynn Clements]

Markus Neteler wrote:

> On Tue, Dec 16, 2008 at 3:33 PM,  <svn_grass at osgeo.org> wrote:
> > Date: 2008-12-16 09:33:27 -0500 (Tue, 16 Dec 2008)
> > New Revision: 34913
> >
> > Modified:
> >   grass/branches/develbranch_6/general/g.gisenv/main.c
> > Log:
> > g.gisenv: -s/n flags added (merge from trunk)
> ...
> > +    flag_s = G_define_flag();
> > +    flag_s->key = 's';
> > +    flag_s->description = _("Use shell syntax (for \"eval\")");
> > +
> > +    flag_n = G_define_flag();
> > +    flag_n->key = 'n';
> > +    flag_n->description = _("Don't use shell syntax");
> > +
> 
> Is -n really needed?

Yes.

> GRASS 6.4.svn (spearfish60): > g.gisenv
> GISDBASE=/home/neteler/grassdata
> LOCATION_NAME=spearfish60
> MAPSET=neteler
> DEBUG=0
> GRASS_GUI=text
> 
> GRASS 6.4.svn (spearfish60): > g.gisenv -s
> GISDBASE='/home/neteler/grassdata';
> LOCATION_NAME='spearfish60';
> MAPSET='neteler';
> DEBUG='0';
> GRASS_GUI='text';
> 
> GRASS 6.4.svn (spearfish60): > g.gisenv -n
> GISDBASE=/home/neteler/grassdata
> LOCATION_NAME=spearfish60
> MAPSET=neteler
> DEBUG=0
> GRASS_GUI=text
> 
> Isn't -n superfluous?

No.
	$ g.gisenv
	GISDBASE=/opt/grass-data
	LOCATION_NAME=spearfish57
	MAPSET=glynn
	GRASS_GUI=text
	
	$ g.gisenv | cat
	GISDBASE='/opt/grass-data';
	LOCATION_NAME='spearfish57';
	MAPSET='glynn';
	GRASS_GUI='text';
	
	$ g.gisenv -n | cat
	GISDBASE=/opt/grass-data
	LOCATION_NAME=spearfish57
	MAPSET=glynn
	GRASS_GUI=text

With neither -s nor -n, the default is -n if stdout is a tty and -s
otherwise (e.g. if stdout is a pipe).

The -n switch is necessary if you're parsing the g.gisenv output
within a script, and you want the "simple" format (i.e. if you're not
using bash's "eval" for parsing).

-- 
Glynn Clements <glynn at gclements.plus.com>