[xml] errors management

[Francesco Gennai <francesco gennai isti cnr it>]

Hi,

I would like to capture any error from LIBXML API
and (if possible) have it in memory to process it 
in my own error/debug routines.

Here is an example of code that can returns more than one error line.

            pctxt.userData = (void *) stderr;
            pctxt.error    = (xmlValidityErrorFunc) fprintf;
            pctxt.warning  = (xmlValidityWarningFunc) fprintf;
            if (!xmlValidateDtd(&pctxt, pdoc, pdtd)) {
                xmlGenericError(xmlGenericErrorContext,
                        "Document %s does not validate against %s\n",
                        xmlFile, dtdFile);

such as:

No declaration for element dst
No declaration for attribute id of element dst
attribute ref line 5 references an unknown ID "foo"
attribute ref line 7 references an unknown ID "foo"

I would like an example how to modify the above code to capture
the error lines in some memory structure (chars array, ....).

Is it possible?

I suppose that it needs to write a function (like *printf functions)
to call in place of fprintf (in the above example).

Is there any example of code?

Francesco

 I tried by changing fprintf with sprintf and stderr with (outerr) a character
 string, but in this case I get
 - only one line of the above errors
 - I have the problem... how much length should be outerr chars array?