December 22, 2000 ISWALNUM 3

### NAME

iswalnum, iswalpha, iswblank, iswcntrl, iswdigit, iswgraph, iswlower, iswprint, iswpunct, iswspace, iswupper, iswxdigit - wide character classification utilities

### LIBRARY

Standard C Library (libc, -lc)

### SYNOPSIS

```int` iswalnum(```wint_t wc`)
```int` iswalpha(```wint_t wc`)
```int` iswblank(```wint_t wc`)
```int` iswcntrl(```wint_t wc`)
```int` iswdigit(```wint_t wc`)
```int` iswgraph(```wint_t wc`)
```int` iswlower(```wint_t wc`)
```int` iswprint(```wint_t wc`)
```int` iswpunct(```wint_t wc`)
```int` iswspace(```wint_t wc`)
```int` iswupper(```wint_t wc`)
```int` iswxdigit(```wint_t wc`)

### DESCRIPTION

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

### 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), isxdigit(3)

### STANDARDS

The functions conform to ISO/IEC 9899:1999 (``ISO C99'') .

### CAVEATS

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