void
get_regerror(int errcode, re_pattern_buffer *compiled, char *func) {

    size_t length = regerror (errcode, compiled, NULL, 0);
    char *buffer = xmalloc (length);

    regerror (errcode, compiled, buffer, length);
    fprintf(stderr, "%s: %s\n", func, buffer);
    free(buffer);
}

#define SET_FASTMAP() \
{ \
  unsigned this_char; \
  \
  memset (fastmap, invert, (1 << BYTEWIDTH)); \
  \
  for (this_char = 0; this_char < strlen (fastmap_string); this_char++)\
    fastmap[fastmap_string[this_char]] = !invert; \
  fastmap['\n'] = match_newline; \
}

void
unformat (char *string) {
  char *pattern;
  struct re_pattern_buffer compiled;
  char fastmap[1 << BYTEWIDTH];
  const char *comperr;
  char *fastmap_string;
  unsigned invert, match_newline;
  struct re_registers *matches;
  int execerr, len, prelen, postlen, slen;

  re_set_syntax (RE_NO_BK_PARENS | RE_NO_BK_VBAR);
  pattern = "(<.>|</.>)";
  invert = 0;
  match_newline = 0;
  fastmap_string = "/<>bi";
  SET_FASTMAP ();

  memset (&compiled, 0, sizeof (compiled));
  comperr = re_compile_pattern(pattern, strlen(pattern), &compiled);
  if (comperr)
    get_regerror((int)*comperr, &compiled, "re_compile_pattern");

  /* Şablon derlendi. Biçim arıtmasına başlayabiliriz. */
  slen = strlen(string);
  compiled.fastmap = fastmap;
  matches = alloca (sizeof(matches) * (compiled.re_nsub + 1));
  while (1) {
    memset (matches, 0, sizeof (matches));
    execerr = re_search (&compiled, string, slen, 0, slen, matches);
    if (execerr == - 1) {
      /* puts ("Eşleşme bulunamadı"); */
      break;
    }
    if (execerr >= 0) {
      len = matches->end[0] - matches->start[0];
      postlen = slen - matches->end[0];
      prelen = matches->start[0];
      strncpy(string + prelen, string + matches->end[0], postlen);
      slen = prelen + postlen;
      string[slen] = '\0';
    } else {
      get_regerror(comperr, &compiled, "re_search");
    }
  }
}