C Programming/wctype.h

In the programming language C,   is a header file in the standard library, containing various functions and macros for classifying and mapping wide characters. The corresponding header for dealing with (normal, non-wide) characters is.

This header declares (from ) the   and   types, and   macro. ( is capable of storing any wide character or the value  .) The type   is also declared, which represents a mapping between characters.

Character classification functions
These functions return non-zero/zero depending on whether or not the argument is in a certain category according to the current locale. POSIX:2008 specifies alternate versions of the functions suffixed with  which take a locale  as an additional argument.

Character mapping functions
These functions take a wide character, and apply some mapping to it.

Other functions
These functions create values for use with other functions, from a string. Note that  is the same as , and   is the same as.