1  /* Test whether a character is a blank.
       2  
       3     Copyright (C) 2009-2023 Free Software Foundation, Inc.
       4  
       5     This file is free software: you can redistribute it and/or modify
       6     it under the terms of the GNU Lesser General Public License as
       7     published by the Free Software Foundation; either version 2.1 of the
       8     License, or (at your option) any later version.
       9  
      10     This file is distributed in the hope that it will be useful,
      11     but WITHOUT ANY WARRANTY; without even the implied warranty of
      12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      13     GNU Lesser General Public License for more details.
      14  
      15     You should have received a copy of the GNU Lesser General Public License
      16     along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
      17  
      18  #include <config.h>
      19  
      20  /* Specification.  */
      21  #include <ctype.h>
      22  
      23  int
      24  isblank (int c)
      25  {
      26    /* On all known platforms, in all predefined locales, isblank(c) is likely
      27       equivalent with  (c == ' ' || c == '\t').  Look at the glibc definition
      28       (in glibc/localedata/locales/i18n): The "blank" characters are '\t', ' ',
      29       U+1680, U+180E, U+2000..U+2006, U+2008..U+200A, U+205F, U+3000, and none
      30       except the first two is present in a common 8-bit encoding.  Therefore
      31       the substitute for other platforms is not more complicated than this.  */
      32    return (c == ' ' || c == '\t');
      33  }