http://sourceware.org/ml/libc-hacker/2002-11/msg00071.html

 When fnmatch detects an invalid multibyte character it should fall back to

 single byte matching, so that "*" has a chance to match such a string.

 Andreas.

 2005-04-12  Andreas Schwab  <schwab@suse.de>

 	* posix/fnmatch.c (fnmatch): If conversion to wide character

 	fails fall back to single byte matching.

 Index: posix/fnmatch.c

 ===================================================================

 diff -durN glibc-2.12.1.orig/posix/fnmatch.c glibc-2.12.1/posix/fnmatch.c

 --- glibc-2.12.1.orig/posix/fnmatch.c	2007-07-28 22:35:00.000000000 +0200

 +++ glibc-2.12.1/posix/fnmatch.c	2009-11-13 00:50:39.000000000 +0100

 @@ -327,6 +327,7 @@

  # if HANDLE_MULTIBYTE

    if (__builtin_expect (MB_CUR_MAX, 1) != 1)

      {

 +      const char *orig_pattern = pattern;

        mbstate_t ps;

        size_t n;

        const char *p;

 @@ -382,10 +383,8 @@

  	  wstring = (wchar_t *) alloca ((n + 1) * sizeof (wchar_t));

  	  n = mbsrtowcs (wstring, &p, n + 1, &ps);

  	  if (__builtin_expect (n == (size_t) -1, 0))

 -	    /* Something wrong.

 -	       XXX Do we have to set `errno' to something which mbsrtows hasn't

 -	       already done?  */

 -	    return -1;

 +	    /* Something wrong.  Fall back to single byte matching.  */

 +	    goto try_singlebyte;

  	  if (p)

  	    {

  	      memset (&ps, '\0', sizeof (ps));

 @@ -397,10 +396,8 @@

  	prepare_wstring:

  	  n = mbsrtowcs (NULL, &string, 0, &ps);

  	  if (__builtin_expect (n == (size_t) -1, 0))

 -	    /* Something wrong.

 -	       XXX Do we have to set `errno' to something which mbsrtows hasn't

 -	       already done?  */

 -	    return -1;

 +	    /* Something wrong.  Fall back to single byte matching.  */

 +	    goto try_singlebyte;

  	  wstring = (wchar_t *) alloca ((n + 1) * sizeof (wchar_t));

  	  assert (mbsinit (&ps));

  	  (void) mbsrtowcs (wstring, &string, n + 1, &ps);

 @@ -408,6 +405,9 @@

        return internal_fnwmatch (wpattern, wstring, wstring + n,

  				flags & FNM_PERIOD, flags, NULL);

 +

 +    try_singlebyte:

 +      pattern = orig_pattern;

      }

  # endif  /* mbstate_t and mbsrtowcs or _LIBC.  */