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Failure to extract information using mini-XML v2.8

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While using miniXML v2.8 (http://www.msweet.org/projects.php?Z3) to read and
process an XML document in a small C program, I came across a problem that
I cannot surmount.

While it is more likely that I'm just not using the API correctly, it may be
that I've uncovered a bug with miniXML. I've reported my problem, with a
suitable test case, to the author, in a bug report.

However, while I wait for a response, I want to hear from other miniXML
users, to see if I've just mis-read or mis-interpreted the API
documentation.

For my demo, I have a dead simple XML document:
  <?xml version="1.0" encoding="utf-8"?><document>Hello, World</document>

The goal of the demo is to extract and print the text contents of the
<document> entity, and it's output /should be/
  Success: "Hello, World"

This simple demo program looks like...

  #include <stdio.h>
  #include <stdlib.h>

  #include <mxml.h>

  int main(void)
  {
    int rc = EXIT_FAILURE;

    mxml_node_t *xml, *doc;
    const char *text;

    xml = mxmlLoadFile(NULL,stdin,MXML_TEXT_CALLBACK);
    doc = mxmlFindElement(xml,xml,"document",NULL,NULL,MXML_DESCEND_FIRST);
    text = mxmlGetText(doc,NULL);

    if (text)
    {
      printf("Success: \"%s\"\n",text);
      rc = EXIT_SUCCESS;
    }
    else puts("Fail");

    return rc;
  }

And here is a trial run and it's output...

  $ cat document.xml
  <?xml version="1.0" encoding="utf-8"?><document>Hello, World</document>

  $ cat document.xml | consumer_s
  Fail

  $ consumer_s <document.xml
  Fail

  $ 

Outside of the obvious error checking, what (if anything) am I doing wrong?
If I read the documentation correctly, the mxmlGetText() call /should/
return a pointer to the text attached to the node that mxmlFindElement()
returned. But, it doesn't. It returns NULL (or the functional equivalent
thereof).

A little more complex code shows that, indeed the mxmlLoadFile() function
loaded the example XML document into a valid miniXML tree (presumably as
TEXT nodes, as specified by the MXML_TEXT_CALLBACK option), and that the
mxmlFindElement() call did indeed locate the "<document>" node.

The miniXML documentation on the mxmlGetText() function reads
> mxmlGetText
> Get the text value for a node or its first child.
> const char *mxmlGetText (
>    mxml_node_t *node,
>    int *whitespace
> );
> Parameters
> node
>           Node to get
> whitespace
>           1 if string is preceded by whitespace, 0
>           otherwise
> Return Value
> Text string or NULL
> Discussion
> NULL is returned if the node (or its first child) is not a
> text node. The "whitespace" argument can be NULL.
> 

What, if anything, am I doing wrong?

-- 
Lew Pitcher
"In Skills, We Trust"
PGP public key available upon request

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Thread

Failure to extract information using mini-XML v2.8 Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2014-04-24 09:30 -0400
  Re: Failure to extract information using mini-XML v2.8 Rainer Weikusat <rweikusat@mobileactivedefense.com> - 2014-04-24 19:04 +0100
    Re: Failure to extract information using mini-XML v2.8 Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2014-04-24 15:16 -0400
      Re: Failure to extract information using mini-XML v2.8 Rainer Weikusat <rweikusat@mobileactivedefense.com> - 2014-04-24 20:45 +0100
        Re: Failure to extract information using mini-XML v2.8 Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2014-04-24 16:02 -0400

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