The term code page is used to refer to a number
of different concepts. Conversely, the set of concepts to which code
page can refer can also be described by a number of other terms.
The concept and implementation of code pages also differ significantly
between Windows, Linux, and the UNIX system.
To describe the types of character data that users can enter and
store in an Rational® ClearQuest® environment,
this discussion uses the following terms:
- A national language support (NLS) provides commands and
library subroutines for a single worldwide system base. In the context
of Rational ClearQuest,
NLS refers to the ability of Rational ClearQuest applications
and databases to input and output data consisting of characters from
any of the supported Rational ClearQuest data
code pages.
- The term character set refers to a set of characters
that a computer application or system supports.
- The term code page, refers to a character set and
the binary values that represent those characters. A computer or application
can use code pages to work with these characters:
- Only the 128 characters of the ASCII character set (suitable for
American English).
- Additional characters used by Eastern and Western European languages,
such as "ä" for German, Swedish and Finnish and "È" for French and
Spanish, and so on.
- Characters from non-European languages such as Hebrew, Japanese,
and Chinese.
- Additional characters required by other languages.
- The term vendor database character set refers to
a character set that the database management system (DBMS) vendor
allows to be stored in the databases for the Rational ClearQuest schema
repository and user data. Individual DBMS vendors use code page, code
set, collation, and charset as synonyms
for this term.
- The term Rational ClearQuest data
code page refers to character set that Rational ClearQuest can
store in a Rational ClearQuest database
set. This character set is equivalent to or a subset of the corresponding
vendor database character set. To set the data code page, you must
select the value compatible with the vendor database character set
that is configured for the vendor database. A schema repository can
support only one data code page.
- The term local character set (generally called the locale on
Linux and the UNIX systems) refers to the character set that can be
entered or displayed in a command-line shell on the system that runs
a Rational ClearQuest application,
for example, the Maintenance Tool, Designer, or Rational ClearQuest client.
On Linux or the UNIX system , the local character set is controlled
by the LANG environment variable. On Windows, it is controlled by
settings in the Regional and Language Options. Other character sets
can be displayed if additional fonts are configured. Also, additional
character data may be entered through an input method editor (IME)
or by cutting and pasting text to the Rational ClearQuest GUI
applications.