Character Manipulation Function

int isspace(int c);

int iswspace(wint_t c);

int _ismbcspace(unsigned int c);

int _istspace(_TINT c);

Internationalization (I18n) Function Overview

The function isspace tests for an white-space character, using the LC_CTYPE category setting of the current locale.

iswspace is the wide character equivalent of isspace, treating c as a multibyte character.

On Windows platforms only, use _ismbcspace for the multibyte character equivalent. It returns nonzero if c is a white-space character within the current multibyte character set.

_istspace is the Windows-only Generic version of the function; with the _MBCS or _UNICODE compiler flags determining its mapping to either _ismbcspace or iswspace.

I18n Issues

Use the appropriate version of the function as required for internationalization support, noting the following:

On ANSI platforms, there is no multibyte version of isspace. Instead, convert the character c to a wide character and call iswspace.

Prior to calling iswspace on ANSI platforms, ensure that the locale is set correctly, since the result of the test condition depends on the locale's LC_CTYPE category setting. On Windows platforms, the iswspace test is independent of locale.

The _ismbcspace function depends on the multibyte code page in effect. By default, the multibyte code page is set to the system-default ANSI code page obtained from the operating system at program startup. Use _getmbcp and _setmbcp to query or change the current multibyte code page, respectively.

Recommended Replacements*

ANSI UTF-8	convert and call iswspace
ANSI UTF-16	iswspace
Microsoft Windows MBCS	_ismbcspace
Microsoft Windows Unicode	iswspace
Microsoft Windows Generic	_istspace

Character Manipulation Functions