iswpunct

iswpunct is a wide-character classification function from the C standard library. It is declared in the header <wctype.h> and takes a wint_t argument representing a wide character. The function tests whether the given wide character is a punctuation character according to the current C locale, as defined by LC_CTYPE.

Return value and behavior: The function returns a nonzero value if the character is a punctuation wide character; otherwise it returns zero. The classification is locale-dependent; in the default C locale, punctuation includes ASCII characters such as ! " # $ % & ' ( ) * + , - . / : ; < = > ? @ [ \ ] ^ _ ` { | } ~. In other locales, additional punctuation marks may be recognized.

Usage context: iswpunct is typically used in text processing and tokenization routines that operate on wide characters. It is the wide-character counterpart to ispunct from <ctype.h> and relies on the program’s current locale to determine punctuation.

Implementation notes: The prototype is int iswpunct(wint_t wc); implementations may vary across platforms (for example, glibc, musl, or Windows), but they conform to the standard behavior of returning nonzero for punctuation wide characters. To use iswpunct, include <wctype.h> and, if locale-aware behavior is required, set the locale with setlocale or similar locale-aware functions.

See also: iswalpha, iswdigit, iswspace, iswpunct, iswupper, iswlower; the narrow-character equivalent is punct in <ctype.h>.