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:"The width of <code>wchar_t</code> is compiler-specific and can be as small as 8 bits. Consequently, programs that need to be portable across any C or C++ compiler should not use <code>wchar_t</code> for storing Unicode text. The <code>wchar_t</code> type is intended for storing compiler-defined wide characters, which may be Unicode characters in some compilers."
:"The width of <code>wchar_t</code> is compiler-specific and can be as small as 8 bits. Consequently, programs that need to be portable across any C or C++ compiler should not use <code>wchar_t</code> for storing Unicode text. The <code>wchar_t</code> type is intended for storing compiler-defined wide characters, which may be Unicode characters in some compilers."


Under [[Windows API]], <code>wchar_t</code> is 16-bit wide. Windows API breaks the ANSI/ISO C standard by not making wchar_t the character type that supports all the system representable characters in a single wchar_t unit; instead, wchar_t in Windows represents a [[UTF-16]] character (or part of it).
Under [[Windows API]], <code>wchar_t</code> is 16-bits wide. Windows API breaks the ANSI/ISO C standard by not making wchar_t the character type that supports all the system representable characters in a single wchar_t unit; instead, wchar_t in Windows represents a [[UTF-16]] character (or part of it).


On [[Unix]]-like systems <code>wchar_t</code> is 32-bit wide.
On [[Unix]]-like systems <code>wchar_t</code> is 32-bits wide.


In [[C standard library|ANSI C library header files]], &lt;wchar.h&gt; and &lt;wctype.h&gt; deal with the wide characters.
In [[C standard library|ANSI C library header files]], &lt;wchar.h&gt; and &lt;wctype.h&gt; deal with the wide characters.

Revision as of 18:06, 23 February 2007

Wide character is a computer programming term. It is a vague term used to represent a datatype that is richer than the traditional 8-bit characters. It is not the same thing as Unicode.

wchar_t is a data type in ANSI/ISO C and some other programming languages that is intended to represent wide characters.

The Unicode standard 4.0 says that

"ANSI/ISO C leaves the semantics of the wide character set to the specific implementation but requires that the characters from the portable C execution set correspond to their wide character equivalents by zero extension."

and that

"The width of wchar_t is compiler-specific and can be as small as 8 bits. Consequently, programs that need to be portable across any C or C++ compiler should not use wchar_t for storing Unicode text. The wchar_t type is intended for storing compiler-defined wide characters, which may be Unicode characters in some compilers."

Under Windows API, wchar_t is 16-bits wide. Windows API breaks the ANSI/ISO C standard by not making wchar_t the character type that supports all the system representable characters in a single wchar_t unit; instead, wchar_t in Windows represents a UTF-16 character (or part of it).

On Unix-like systems wchar_t is 32-bits wide.

In ANSI C library header files, <wchar.h> and <wctype.h> deal with the wide characters.