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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.the variable of this type store 2 bytes character ode with value in the range from 0 to 65,536

wchar_t is a data type in ANSI/ISO C, 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 Win32, wchar_t is 16 bits wide and represents a UTF-16 code unit. On Unix-like systems wchar_t is commonly 32 bits wide and represents a UTF-32 code unit.

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

Python

According to the Python documentation, Python sometimes uses wchar_t as the basis for it's character type Py_UNICODE. It depends on whether wchar_t is "compatible with the chosen Python Unicode build variant" on that system. ^[1]

Syntax

wchar_t variable = 'value'; // storing a 16bit character code and value should be either in hexadecimal or single ACII character wchar_t variable('value');

Functions

There are several functions in C's stdlib.h to help with wchar_t's.

wctomb() - wide character to multibyte character ^[2]
mbtowc() - multibyte character to wide char ^[3]
wcstombs() - wide-char string to multibyte character string ^[4]
mbstowcs() - multibyte character string to wide-char string ^[5]
mblen() - number of bytes in a multibyte character ^[6]

The author of GNU libc advises to avoid these due to the 'state' mechanism they involve, and instead suggests the 'restartable' mbsrtowcs et al functions. ^[7]

External links

The Unicode Standard, Version 4.0 - online edition

Notes

^ http://docs.python.org/c-api/unicode.html accessed 2009 12 19
^ C++ Resources Network - wctomb, access 2009 12 15
^ C++ Resources Network - mbtowc, access 2009 12 15
^ C++ Resources Network - wcstombs, access 2009 12 15
^ C++ Resources Network - mbstowcs, access 2009 12 15
^ C++ Resources Network - mblen, access 2009 12 15
^ GNU.org libc source code, libc/stdlib/mbstowcs.c, accessed 2009 12 15

This programming-language-related article is a stub. You can help Wikipedia by expanding it.

[1] ttp://docs.python.org/c-api/unicode.html accessed 2009 12 19

[2] C++ Resources Network - wctomb, access 2009 12 15

[3] C++ Resources Network - mbtowc, access 2009 12 15

[4] C++ Resources Network - wcstombs, access 2009 12 15

[5] C++ Resources Network - mbstowcs, access 2009 12 15

[6] C++ Resources Network - mblen, access 2009 12 15

[7] GNU.org libc source code, libc/stdlib/mbstowcs.c, accessed 2009 12 15

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-'''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]].
+'''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]].the variable of this type store 2 bytes character ode with value in the range from 0 to 65,536
 <code>wchar_t</code> is a data type in ANSI/ISO [[C (programming language)|C]], ANSI/ISO [[C++]], and some other [[programming language]]s that is intended to represent wide characters.
@@ Line 18: / Line 18: @@
 According to the Python documentation, [[Python_(programming_language) | Python]] sometimes uses wchar_t as the basis for it's character type Py_UNICODE. It depends on whether wchar_t is "compatible with the chosen Python Unicode build variant" on that system. <ref>http://docs.python.org/c-api/unicode.html accessed 2009 12 19</ref>
+''' Syntax '''
+wchar_t variable = 'value'; // storing a 16bit character code and value should be either in hexadecimal or single ACII character
+wchar_t variable('value');
 ==Functions==