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iswctype(3)
NAME
  iswctype - Determine the properties of a wide character

SYNOPSIS
  #include <wctype.h>

  int iswctype(
	  wint_t wc,
	  wctype_t wc_prop );

  The XPG4 standard specifies that applications define this function by
  including wchar.h rather than wctype.h, which is required by the current
  version of the ISO C standard. Both include statements are supported.

LIBRARY
  Standard C Library (libc)

STANDARDS
  Interfaces documented on this reference page conform to industry standards
  as follows:

  iswctype(): ISO C, XPG4

  Refer to the standards(5) reference page for more information about
  industry standards and associated tags.

PARAMETERS
  wc  Specifies the wide character to be tested.

  wc_prop
      Specifies a handle for a valid wide character property name as defined
      in the current locale.

DESCRIPTION
  The iswctype() function tests the wide character specified by the wc
  parameter to determine if it has the property specified by the wc_prop
  parameter. The wctype() function associates a character property with a
  wctype_t handle. You should get the value of the wc_prop parameter from a
  call to wctype() before using it in a call to iswctype(). The iswctype()
  function is defined for the wide-character null and for values in the
  character range of the current code set defined in the current locale.

  Using an iswclass function, such as iswalnum(), is equivalent to using the
  iswctype() and wctype() functions to test for a basic property, such as
  alnum. However, iswctype() and wctype() can test wide characters against
  any class defined in a locale; the functions are not limited to testing for
  basic properties.

RETURN VALUES
  If the wc parameter has the property specified by the wc_prop parameter,
  the iswctype() function returns a nonzero value. If the value specified by
  the wc parameter does not have the property specified by the wc_prop
  parameter, the iswctype() function returns a value of 0 (zero). If the
  value specified by the wc parameter is not in the function's domain, the
  result is undefined. If the value specified by the wc_prop parameter is not
  valid, the result is undefined. The value of the wc_prop parameter can be
  invalid because it was not obtained by a call to the wctype() function. The
  wc_prop value can also be invalidated by an intervening call to the
  setlocale() function that has affected the LC_CTYPE environment variable.

  If the input value (wc) is not in the range of wide characters defined by
  the current locale, the result is undefined. To check the range of input
  values, compile applications with standard compile options such as -
  DOPEN_SOURCE. If the application compiles with any of the standard compile
  options, the interfaces documented in this reference page resolve as
  functions, which perform internal range checking.  A default compilation
  (that is, no standard compile options specified) results in resolution of
  the interfaces as macros, which do not perform internal range checking.

EXAMPLES
   1.  The following example tests to determine if a wide character belongs
       to the class of blank characters as defined for the current locale.
       In this case, the required call to wctype() is included directly as
       the wc_prop parameter:

	    iswctype(wc, wctype("blank"));

   2.  The following example tests to determine if a wide character is an
       uppercase character as defined by the current locale. In this case,
       the required call to wctype() is specified through a handle:

	    int yes_or_no;
	    wint_t wc;
	    wctype_t property_test;
	      .
	      .
	      .
	    property_test=wctype("upper");
	    yes_or_no=iswctype(wc,property_test);

SEE ALSO
  Functions: ctype(3), towctrans(3), wctrans(3), wctype(3), setlocale(3),
  iswalnum(3)

Index for Section 3

Alphabetical listing for I

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