Re: Debugging Bison Under Windows

[Ramaswamy R]

You should be able to use the function yyerror to capture the debug
messages. The function prototype would be like this in a re-entrant parser -


int yyerror(void *ctxt, const char *msg)
{
 if ( 0 == yytext[0] )
   return fprintf(stderr, "\n%s.", msg);
 else
   return fprintf(stderr, "\n%s at '%s'.", msg, asntext);
}

I believe the ctxt would not be there in a non re-entrant version (globals
being used if context information is required). You can use this function to
do what you want with the message. Hope this helps.

Regards
Ramaswamy
--
"Chaos is the rule in nature, not an exception"

http://ramaswamy.r.googlepages.com

On 10/26/06, Bob Smith <address@hidden> wrote:

> Using Bison version 2.3 (Cygwin), I have incorporated the resulting C
> file into a Windows app, however, I'm having trouble figuring out how
> to debug the parser.  I've #define YYDEBUG 1, and set yydebug to 1,
> but the output is going to fprintf (stderr, ...) which doesn't help a
> Windows app.
>
> It seems that the formatting and output of the debugging information
> are all bound up into one #define.  I want the first part, but not the
> second.
>
> I already have a debugging window for my app defined, so I'd like to
> capture the output and display it in that window (it's a Listbox).
>
> * I tried AllocConsole () hoping that the stderr output would go
> there, but nothing was displayed.
>
> * I tried redefining yacc.c, and then using -S myyacc.c, but it
> appears to rely upon an external program m4 which didn't seem to get
> called, so the C compiler choked on the m4 stuff.  That was puzzling
> as I would think that it would be called for the default skeleton
> (yacc.c).
>
> * I tried defining YYFPRINTF but I couldn't come up with anything that
> worked, mostly because of the variable number of arguments.
>
> I'm sure that you clever people have solved this tricky problem
> before.  Any help you can provide is greatly appreciated.
> --
> _______________________________________________________________
> Bob Smith - address@hidden - http://www.sudleyplace.com
>
>
> _______________________________________________
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