Re: [Help-glpk] [PATCH] determine whether we are handling an error

[Jeroen Demeyer]

On 2015-11-05 22:20, Heinrich Schuchardt wrote:
> Hello Jeroen,
>
> could you, please, describe the use case for the patch.

My use case is really for using GLPK through SageMath, which is a 
mathematical program with an interactive Python interface. I want to 
convert GLPK errors to Python exceptions. For this I install an error 
hook and a term hook. But I need to distinguish between normal messages 
and error messages.

> Currently both normal messages and error messages are sent to stdout,
> which does not match usual usage of output streams.
>
> I propose to store the information if an error message is written in
> env->term_out and to use a new value GLP_ERROR = 2 to indicate an error
> message.
>
> This value then should be used in glp_puts to decide if a message shall
> be sent to stdout or stderr.
>
> An API function could be provided to read env->term_out. The return
> value could be used in the terminal hook function.

Sure, I don't really care so much *how* this feature is added. I 
implemented it the way I did mainly because it was the simplest solution.


Jeroen.