iswalnum(), iswalpha(), iswblank(), iswcntrl(), iswdigit(), iswgraph(), iswlower(), iswprint(), iswpunct(), iswspace(), iswupper(), iswxdigit()

Tests for membership in subsets of the wide-character set.

  #include <wctype.h>  
  int iswalnum(wint_t c);  
  int iswalpha(wint_t c);  
  int iswblank(wint_t c);  
  int iswcntrl(wint_t c);  
  int iswdigit(wint_t c);  
  int iswgraph(wint_t c);  
  int iswlower(wint_t c);  
  int iswprint(wint_t c);  
  int iswpunct(wint_t c);  
  int iswspace(wint_t c);  
  int iswupper(wint_t c);  
  int iswxdigit(wint_t c);

Parameter

c

A wide-character value to test.

Remarks

These functions provide the same facilities as their counterparts in the ctype.h header file. However, these functions test wide characters and the EOF value.

The c argument is of type wint_t so that the EOF value, which is outside the range of the wchar_t type, may also be tested.

The table below lists these functions and their counterparts in ctype.h.

Table 1. Wide Character Testing Functions
Function	ctype.h Equivalent
`iswalnum(c)`	`isalnum(c)`
`iswalpha(c)`	`isalpha(c)`
`iswblank(c)`	`isblank(c)`
`iswcntrl(c)`	`iscntrl(c)`
`iswdigit(c)`	`isdigit(c)`
`iswgraph(c)`	`isgraph(c)`
`iswlower(c)`	`islower(c)`
`iswprint(c)`	`isprint(c)`
`iswpunct(c)`	`ispunct(c)`
`iswspace(c)`	`isspace(c)`
`iswupper(c)`	`isupper(c)`
`iswxdigit(c)`	`isxdigit(c)`