Re: non-interactive usage and color error messages

[Ethan M. <merritt@u.washington.edu>]

On Friday 23 October 2009 10:05:49 Petr Mikulik wrote:
> It is neither nice or useful when gnuplot is writing error message such as:
> 
> Error: terminal "dumb" does not support continuous colors.
> This terminal does not support palette-based images.
> This terminal does not support rgb images.
> This terminal does not support filled polygons.
> 
> when in non-interactive mode (e.g. driven via Octave). They are actually 
> just warnings, not errors.

Comments:

I'm not an Octave user, so maybe I am missing something.
Would that actually work?  Isn't an Octave session also interactive?

Every message that is generated by 
  fprintf(stderr,ERROR_NOTICE(foo))
should be changed to use int_warn() instead.
I think these were added by Dan Sebald at a time when he was not familiar
with the existing mechanisms and conventions.

Having done that, we could put the   "if (interactive) ..."
test in int_warn() and cover all of these messages in one go.

Or maybe we could add a command line option
   gnuplot -nowarnings
and/or an internal command
   unset warnings


> I propose to surround the respective code by
> 
> if (interactive)
>   ...error message...
> 
> What do you think? Are there any other messages that would deserve the same 
> care?


-- 
Ethan A Merritt