[GRASSLIST:6010] Re: Problem using r.in.ascii

[Glynn Clements]

Markus Neteler wrote:

> > Never mind this message.  After fighting with it all day yesterday, I 
> > discovered a mask file that I had forgotten about because I've slept since 
> > then.  I only figured it out about it when I tried to draw a new mask file 
> > for surfacing, and THAT wouldn't display.
> > 
> > NUTS!!
> 
> What if there were the work 'MASK' or just 'M' in the GRASS prompt?
> I was fighing with the same problem recently ...
> 
> Something like
>  GRASS:~ >
> and
>  GRASS(M):~ >
> 
> in case a MASK is present. Maybe there is a possibility to
> add a file check to
> PS1='GRASS:\w > '
> ?

With bash, the variable PROMPT_COMMAND can be used to specify a
command which is run before printing the prompt. E.g.

PROMPT_COMMAND='if r.info MASK &> /dev/null ; then echo -n "GRASS(M):" ; else echo -n "GRASS:" ; fi'
PS1='\w '

Except that the above will repeatedly send you email with the error
message from r.info when MASK doesn't exist. Ideally, you want a
dedicated utility which tests for the existence of a mask.

-- 
Glynn Clements <glynn.clements at virgin.net>