Glossary- ANSI
American National Standards Institute. ANSI proposes standard
definitions for different computing languages. The most recent standard for
the C language, prepared by the ANSI C X3J11 Committee, includes library functions
for computing with multibyte characters for international usage, as well as
a new data type, wchar_t, for dealing with four-byte characters.
This standard is not completed, so it is referred to as the "proposed
ANSI C standard," or ANSI C-X3J11.
- ASCII
American Standard Code for Information Interchange. A seven-bit
code containing English upper and lowercase letters, punctuation, numbers
and control codes. The eighth bit in each byte is used by different applications
for parity checking, communication and message passing protocols, compacting
data, or other purposes. Applications that are intended to be internationalized
cannot utilize this bit if they are going to use multiple code sets or multibyte
characters, and utilities that handle multiple code sets or multibyte characters.
- BIG5
A commonly used code set in Taiwan.
- Category
In the Traditional Chinese Solaris documentation set, category
is related to localization. A category is a portion of a country's language
representation and cultural conventions. For instance, the date is often represented
in the U.S. as month, day, year; while in another country it might be day, month, year.
The date and time can be thought of as one category of a local language. Categories
also refer to the program categories, the environment variables that are related
to categories, and the ANSI localization tables for each category.
- Character Set
A character set is defined as a set of elements used for the
organization, control, or representation of data. Character sets may be composed
of alphabets, ideograms, or other units. This may seem a bit open-ended, but
character sets may contain other character sets, which makes the boundaries
unclear. For example, the CNS 11643 character set contains English, Greek,
and Chinese character sets in addition to Chinese radicals and many other
characters.
- CNS
Taiwan's Chinese National Standard. This is the Taiwan analogue
to ASCII. In this document set, it refers to the code set defined by CNS 11643.
It contains the Chinese characters, phonetic symbols and radicals, control
codes, punctuation, and western alphabets, including Roman and Greek characters.
Each character is two bytes long, with the highest or most significant bit
of each byte set to zero. In other words, it uses the lower seven bits of
each byte. Due to the size of the Taiwan Chinese character set, they are divided
into multiple codeplanes, with the default plane containing the most commonly
used characters. ISO 2022 provides mechanisms for shifting from one codeplane
to another.
After its revision in 1992, CNS 11643 defines 48,000
characters, which are divided among codeplanes 1-7, codeplanes 8-16 are undefined,
but are included in the code set architecture. codeplanes 1 and
2 (common and rarely used characters) are unaffected by the revision. Characters
that were in codeplane 14, a provisional user-defined plane, have been standardized
into codeplane 3, with the overflow in codeplane 4.
- Code set
Also called a coded character set, this is a set of unambiguous
rules that establishes a character set and the one-to-one relationship between
each character in the character set and its bit representation. For example,
the English character set, including punctuation and numbers, can be mapped
to the ASCII code set in such a way that each character corresponds to only
one bit code, and no bit code corresponds to more than one character.
- EUC
Extended UNIX Code. Describes four code sets modelled on ISO-2022.
Each code set can contain one or more different character sets, like the Hangul
and Hanja character sets in KS C 5601. The four code sets are referred to
as codesets 0, 1, 2, and 3, and in this text they are sometimes abbreviated
as cs0, cs1, cs2, and cs3. Other internationalization efforts sometimes call
these g0, g1, g2, and g3. Codeset 0 is also called the primary code set, and
codesets 1, 2, and 3 are called the supplementary code sets. In the Korean
and Chinese implementations of the EUC codes, the primary code set (cs0) contains
ASCII and begins with a zero in the most significant bit.
- EUC-CNS
The EUC representation of CNS 11643. For Codeset 1, this is
the normal CNS code with a one in the most significant bit of each byte. In
other words, EUC-CNS equals CNS plus 0x8080. For example, the CNS character
0x212A becomes the EUC-CNS character 0xA1AA. Or in binary, 00100001 00101010
becomes 10100001 10101010. For Codesets 2 and 3, characters are also prefixed
by single shift bytes SS2 and SS3. In addition, codeset 2 requires a codeplane
byte. The code of a codeset-2 character is SS2 followed by codeplane byte
followed by EUC-CNS. The codeplane byte is plane number added to 0xA0; for
example plane 2 has codeplane bye 0xA2.
- ISO
International Standards Organization. Composed of a number
of professional societies and companies, this organization studies and makes
recommendations on internationalization issues. ISO 2022 proposes and describes
the Extended UNIX Codes. Other ISO proposals include the European 8-bit code
and communication protocols for internationalization.
- Locale
A locale describes a language or cultural environment. Its
setting affects the display or manipulation of language-dependent features.
Traditional Chinese Solaris software provides C for U.S.A, zh_TW
for Traditional Chinese extended UNIX code, and zh_TW.BIG5 for the Traditional Chinese Big5 locale.
- POSIX
Portable Operating System for Computer Environments. An IEEE
standards group comprising seven committees that create documents for standardizing
and internationalizing UNIX. POSIX document 1003.1 deals with the kernel and
system calls. 1003.2 concerns the C-shell and standard libraries. The other
five deal with real-time computing, communications and networking, and other
issues.
- Unicode
The international character set and encoding developed by
the Unicode Consortium.
- Wide Character Code (WC)
A constant-width four-byte code, called WC in Asian Solaris
documentation, for the internal representation of EUC codes using the new
ANSI-C data type wchar_t. Although EUC does not specify
limits on the size of the supplementary code sets (codeset 0 is always one
byte), WC specifies a character as four bytes. Standardizing on four bytes
takes up more memory space than necessary if the environment is primarily
ASCII, but it also speeds processing time for strings of mixed characters;
the 1000th character always begins at byte 4000 (and the 0th character starts
at byte 0). This is useful for any type of indexing in applications.
- X/Open
X/Open started as a consortium of international UNIX vendors
from Europe, USA, and Asia. It is now one of the major standards organizations
like POSIX and ANSI; source of X/Open System Interface Portability
Guide.
|