The UNIX command locale -a can be used to display all supported character sets on your system.įor more information, refer to the man pages for "locale" and "setlocale."
If this line is not present, or if LANG is either not set or is set to NULL, the default locale "C" is used. It selects the character set indicated by the environment variable LANG as the one to be used by X/Open compliant character handling functions. Use the following procedure to set the locale to a different character set:Īdd the following line at the very beginning of applications that use double-byte character sets: The default locale "C" corresponds to the 7-bit US-ASCII character set. The drivers normally use the character set defined by the default locale "C" unless explicitly pointed to another character set. The DataDirect Connect Series for ODBC UNIX and Linux drivers can use double-byte character sets. DBCS encoding provided a cross-platform mechanism for building multilingual applications. The DBCS environment also introduced the concept of an operating system code page that identified how characters would be encoded into byte sequences in a particular computing environment. With DBCS, characters map to either one byte (for example, American ASCII characters) or two bytes (for example, Asian characters). The extension, known as the Double-Byte Character Set (DBCS), allowed existing applications to function without change, but provided for the use of additional characters, including complex Asian characters. Today, ASCII refers to either the 7-bit or 8-bit encoding of characters.Īs the need increased for applications with additional international support, ANSI again increased the functionality of ASCII by developing an extension to accommodate multilingual software. Using the eighth bit to extend the total range of characters to 256 added support for most European characters. This version of ASCII could not account for European characters, and was completely inadequate for Asian characters. The initial version of ASCII used only 7 of the 8 bits available in a byte, which meant that applications could use only 128 different characters. ASCII encoding was convenient for programmers because each ASCII character could be stored as a byte. Most legacy computing environments have used ASCII character encoding developed by the ANSI standards body to store and manipulate character strings inside software applications.
Software developers have used a number of character encodings, from ASCII to Unicode, to solve the many problems that arise when developing software applications that can be used worldwide. Unfortunately, understanding Unicode is not as simple as its name would indicate. Most developers know that Unicode is a standard encoding that can be used to support multi-lingual character sets.
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