Reference

iswalnum(3)

wide character classification utilities

NAME

iswalnum, iswalpha, iswascii, iswblank, iswcntrl, iswdigit, iswgraph, iswhexnumber, iswideogram, iswlower, iswnumber, iswphonogram, iswprint, iswpunct, iswrune, iswspace, iswspecial, iswupper, iswxdigit – wide character classification utilities

LIBRARY

Standard C Library (libc, -lc)

SYNOPSIS

#include <wctype.h>

int

iswalnum(wint_t wc);

int

iswalpha(wint_t wc);

int

iswascii(wint_t wc);

int

iswblank(wint_t wc);

int

iswcntrl(wint_t wc);

int

iswdigit(wint_t wc);

int

iswgraph(wint_t wc);

int

iswhexnumber(wint_t wc);

int

iswideogram(wint_t wc);

int

iswlower(wint_t wc);

int

iswnumber(wint_t wc);

int

iswphonogram(wint_t wc);

int

iswprint(wint_t wc);

int

iswpunct(wint_t wc);

int

iswrune(wint_t wc);

int

iswspace(wint_t wc);

int

iswspecial(wint_t wc);

int

iswupper(wint_t wc);

int

iswxdigit(wint_t wc);

DESCRIPTION

The above functions are character classification utility functions, for use with wide characters (wchar_t or wint_t). See the description for the similarly-named single byte classification functions (such as isalnum(3)), for details.

Extended locale versions of these functions are documented in iswalnum_l(3). See xlocale(3) for more information.

RETURN VALUES

The functions return zero if the character tests false and return non-zero if the character tests true.

SEE ALSO

isalnum(3), isalpha(3), isascii(3), isblank(3), iscntrl(3), isdigit(3), isgraph(3), ishexnumber(3), isideogram(3), islower(3), isnumber(3), isphonogram(3), isprint(3), ispunct(3), isrune(3), isspace(3), isspecial(3), isupper(3), iswalnum_l(3), isxdigit(3), wctype(3)

STANDARDS

These functions conform to IEEE Std 1003.1-2001 (“POSIX.1”), except iswascii(), iswhexnumber(), iswideogram(), iswnumber(), iswphonogram(), iswrune(), and iswspecial(), which are FreeBSD extensions.

CAVEATS

The result of these functions is undefined unless the argument is WEOF or a valid wchar_t value for the current locale.

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