# iswblank.m4 serial 4

dnl Copyright (C) 2011-2017 Free Software Foundation, Inc.

dnl This file is free software; the Free Software Foundation

dnl gives unlimited permission to copy and/or distribute it,

dnl with or without modifications, as long as this notice is preserved.

AC_DEFUN([gl_FUNC_ISWBLANK],

[

  AC_REQUIRE([gl_WCTYPE_H_DEFAULTS])

  AC_REQUIRE([gl_WCTYPE_H])

  dnl Persuade glibc <wctype.h> to declare iswblank().

  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])

  AC_CHECK_FUNCS_ONCE([iswblank])

  AC_CHECK_DECLS([iswblank], , , [[

/* Tru64 with Desktop Toolkit C has a bug: <stdio.h> must be included before

   <wchar.h>.

   BSD/OS 4.0.1 has a bug: <stddef.h>, <stdio.h> and <time.h> must be included

   before <wchar.h>.  */

#include <stddef.h>

#include <stdio.h>

#include <time.h>

#include <wchar.h>

#include <wctype.h>

]])

  if test $ac_cv_func_iswblank = no; then

    HAVE_ISWBLANK=0

    if test $ac_cv_have_decl_iswblank = yes; then

      REPLACE_ISWBLANK=1

    fi

  fi

  if test $HAVE_ISWCNTRL = 0 || test $REPLACE_ISWCNTRL = 1; then

    dnl Redefine all of iswcntrl, ..., towupper in <wctype.h>.

    :

  else

    if test $HAVE_ISWBLANK = 0 || test $REPLACE_ISWBLANK = 1; then

      dnl Redefine only iswblank.

      :

    fi

  fi

])