[GRASS5] Environment variable listings...

[Eric G. Miller]

Do you think people would find it useful if g.gisenv could list all of
the known environment variables with a bit of information about them?

I've hacked my copy of g.gisenv to do this via an "-l" flag.  Output is
like:

----------------------<snippet>----------------------------------
VARIABLE    :: GRASS_FP_DOUBLE [(nil)]
DESCRIPTION :: Default type of floating point representation for floating point rasters.
DOMAIN      :: DCELL_TYPE | FCELL_TYPE
EXAMPLE     :: GRASS_FP_DOUBLE=FCELL_TYPE

Press Enter to continue ('q' to quit)> 

VARIABLE    :: GRASS_HEIGHT [2400]
DESCRIPTION :: Define height of CELL driver output
DOMAIN      :: Positive integer
EXAMPLE     :: GRASS_HEIGHT=480

...
----------------------<snippet>----------------------------------

It pauses between entries iff isatty(1) is true.  It does not interfere
with the get/set behavior currently in place.

Seems it's never easy enough to figure out what environment variables
are available for controlling behaviors...  Developer's can easily add
to the struct array if there's a module that recognizes a certain
variable and it's not yet "registered".

Opinions?

-- 
Eric G. Miller <egm2 at jps.net>