text: /* This is simple demonstration of how to use expat. This program
     reads an XML document from standard input and writes a line with
     the name of each element to standard output indenting child
     elements by one tab stop more than their parent element.
  */
  
  #include <stdio.h>
  #include "expat.h"
  
  static void
  startElement(void *userData, const char *name, const char **atts)
  {
    int i;
    int *depthPtr = userData;
    for (i = 0; i < *depthPtr; i++)
      putchar('\t');
    puts(name);
    *depthPtr += 1;
  }
  
  static void
  endElement(void *userData, const char *name)
  {
    int *depthPtr = userData;
    *depthPtr -= 1;
  }
  
  int
  main(int argc, char *argv[])
  {
    char buf[BUFSIZ];
    XML_Parser parser = XML_ParserCreate(NULL);
    int done;
    int depth = 0;
    XML_SetUserData(parser, &depth);
    XML_SetElementHandler(parser, startElement, endElement);
    do {
      size_t len = fread(buf, 1, sizeof(buf), stdin);
      done = len < sizeof(buf);
      if (XML_Parse(parser, buf, len, done) == XML_STATUS_ERROR) {
        fprintf(stderr,
                "%s at line %d\n",
                XML_ErrorString(XML_GetErrorCode(parser)),
                XML_GetCurrentLineNumber(parser));
        return 1;
      }
    } while (!done);
    XML_ParserFree(parser);
    return 0;
  }
  