ISWALNUM(3) | Library Functions Manual | ISWALNUM(3)

# NAME

`iswalnum`, `iswalnum_l`, `iswalpha`, `iswalpha_l`, `iswblank`, `iswblank_l`, `iswcntrl`, `iswcntrl_l`, `iswdigit`, `iswdigit_l`, `iswgraph`, `iswgraph_l`, `iswlower`, `iswlower_l`, `iswprint`, `iswprint_l`, `iswpunct`, `iswpunct_l`, `iswspace`, `iswspace_l`, `iswupper`, `iswupper_l`, `iswxdigit`, `iswxdigit_l` — wide-character classification utilities

# SYNOPSIS

`#include <wctype.h>`

int
`iswalnum`(wint_t wc);

int
`iswalnum_l`(wint_t wc, locale_t locale);

int
`iswalpha`(wint_t wc);

int
`iswalpha_l`(wint_t wc, locale_t locale);

int
`iswblank`(wint_t wc);

int
`iswblank_l`(wint_t wc, locale_t locale);

int
`iswcntrl`(wint_t wc);

int
`iswcntrl_l`(wint_t wc, locale_t locale);

int
`iswdigit`(wint_t wc);

int
`iswdigit_l`(wint_t wc, locale_t locale);

int
`iswgraph`(wint_t wc);

int
`iswgraph_l`(wint_t wc, locale_t locale);

int
`iswlower`(wint_t wc);

int
`iswlower_l`(wint_t wc, locale_t locale);

int
`iswprint`(wint_t wc);

int
`iswprint_l`(wint_t wc, locale_t locale);

int
`iswpunct`(wint_t wc);

int
`iswpunct_l`(wint_t wc, locale_t locale);

int
`iswspace`(wint_t wc);

int
`iswspace_l`(wint_t wc, locale_t locale);

int
`iswupper`(wint_t wc);

int
`iswupper_l`(wint_t wc, locale_t locale);

int
`iswxdigit`(wint_t wc);

int
`iswxdigit_l`(wint_t wc, locale_t locale);

# DESCRIPTION

The functions are character classification utility functions, for use with wide characters (wchar_t or wint_t). See the description of singlebyte classification functions, like isalnum(3), for details.

The two-argument variants use the specified locale, while the others use the thread-specific locale set with uselocale(3), falling back to the global locale set with setlocale(3).

# 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), isblank(3), iscntrl(3), isdigit(3), isgraph(3), islower(3), isprint(3), ispunct(3), isspace(3), isupper(3), iswctype(3), isxdigit(3), newlocale(3), setlocale(3), towlower(3)

# STANDARDS

The one-argument functions conform to ISO/IEC 9899:1999 (“ISO C99”), the two-argument functions to IEEE Std 1003.1-2008 (“POSIX.1”).

# CAVEATS

The argument wc must be `WEOF` or a valid wchar_t value with the current locale; otherwise, the result is undefined.

September 5, 2017 | Debian