environ.5int

来自「<B>Digital的Unix操作系统VAX 4.2源码</B>」· 5INT 代码 · 共 293 行

.TH environ 5int
.SH Name 
environ \- natural language support (NLS) environment variables 
.SH Description 
.NXR "environment" "variables"
.NXR "NLS (natural language support) environment" "variables"
The international environment variables are defined for the ULTRIX
system and are additional to those described in 
the ULTRIX reference pages, Sections 2 (system calls) and 3 (routines),
and the 
.MS environ 7 
reference page.
The international variables are made available to a process by
.PN exec .
.PP
This reference page is divided into two sections.  The first section
describes environment variables that can control the locale setting.  
The
second section describes the variables that control where the
.PN catopen
function searches for message catalogs and where the
.PN setlocale
function searches for language databases.
.SS "Environment Variables That Control the Locale Setting"
The LANG, LC_COLLATE, LC_TYPE, LC_NUMERIC, LC_TIME, and LC_MONETARY
environment variables can control the locale setting.  You define
these variables using the same format as the 
.I locale
argument to the
.PN setlocale 
function.  The following shows the format you use:
.EX
language[_territory[.codeset]][@modifier]
.EE
In 
.IR language , 
you specify the native language of the
user.  You can optionally specify the user's dialect and codeset using
.I _territory 
and 
.IR codeset .
For example, the following definition of LANG specifies the French native 
language, as spoken in
France (as opposed to in Switzerland), and the Digital Multinational
Character Set:
.EX 0
LANG = FRE_FR.MCS
.EE
In 
.IR @modifier , 
you specify a specific instance of localization data within a single category. 
For example, using 
.IR @modifier  , 
you can specify telephone directory ordering of data, as opposed to dictionary 
ordering of data.  You cannot use 
.I @modifier
to define the LANG variable.
.PP
The following list describes the environment variables that control
the locale setting:
.IP LANG 15
Identifies the user's requirements for native language, local customs,
and coded character set. At run time, you can bind the user's language 
requirements, as specified by the setting of
.PN LANG ,
to the execution of a program by calling
.PN setlocale ,
as follows:
.EX
setlocale (LC_ALL, "");
.EE
.IP
If 
.PN LANG
is not defined in the current environment, the locale defaults to the C locale. 
For more information on the C locale, see the
.I POSIX Conformance Document. 
.IP
System administrators can define 
.PN LANG
to provide a  default setting for the system as a whole, or user's can define
.PN LANG
individually using standard command interpreter facilities.  
.IP LC_COLLATE
Contains the user's requirements for language, territory, and codeset 
for the character collation format.
.PN LC_COLLATE
affects the behavior of regular expressions and the string collation
functions in
.PN strcoll
and
.PN strxfrm .
If 
.PN LC_COLLATE
is not defined in the current environment,
.PN LANG
provides the necessary default.
.IP LC_CTYPE
Contains the user's requirements for language, territory, and codeset for
the character classification and conversion format.
.PN LC_CTYPE
affects the behavior of the character-handling functions in
.PN conv
and
.PN ctype .
If 
.PN LC_CTYPE
is not defined in the current environment,
.PN LANG
provides the necessary default.
.IP LC_MONETARY
Contains the user's requirements for language, territory, and codeset for
the monetary format.
.PN LC_MONETARY
affects the currency string in 
.PN nl_langinfo .
If 
.PN LC_MONETARY
is not defined in the current environment,
.PN LANG
provides the necessary default.
.IP LC_NUMERIC
Contains the user's requirements for language, territory, and codeset for
the numeric data presentation format.
.PN LC_NUMERIC
affects the radix and thousands separator character for the
formatted I/O functions in
.PN printf ,
.PN scanf ,
.PN nl_printf ,
.PN nl_scanf ,
and the string conversion functions in
.PN ecvt
and
.PN atol .
If 
.PN LC_NUMERIC
is not defined in the current environment,
.PN LANG
provides the necessary default.
.IP LC_TIME
Contains the user's requirements for language, territory, and codeset for
the time format.
.PN LC_TIME
affects the behavior of the time functions in
.PN strftime .
If 
.PN LC_TIME
is not defined in the current environment,
.PN LANG
provides the necessary default.
.SS Environment Variables That Specify Locations
The NLSPATH and INTLINFO environment variables control where the
.PN catopen
and 
.PN setlocale
functions search for message catalogs and the language databases.
You define these variables using a pathname or set of pathnames.  The
pathnames can contain variable elements, called substitution fields,
that allow your program or the setting of other environment variables to 
affect the setting of NLSPATH and INTLINFO.  The following shows the format 
you use to define these variables:
.EX
\fIvariable-name\fP="[:][/\fIdirectory\fP][/\fIsubstitution field\fP]
           [/\fIfile-name\fP][:\fIalternate-pathname\fP][:..."
.EE
You specify either NLSPATH or INTLINFO in place of
.IR variable-name .
.PP
A colon (:) that precedes other parts of any pathname in the definition
specifies the current directory.
.PP
In 
.IR directory , 
you can specify a specific directory in which the
function searches.  If you need the environment variable to be
flexible, you can use a substitution field in place of or with
directory names.  A substitution field consists of a percent sign (%),
followed by a code letter.  
The substitution fields you can use are as follows:
.IP %N 5
The value of the
.I name
argument you pass to
.PN catopen 
.IP %L
The value of
the LANG environment variable
.IP %l
The
.I language
element from LANG
.IP %t
The
.I territory
element from LANG
.IP %c
The
.I codeset
element from LANG
.IP %%
A literal percent sign
.PP
If a substitution field you specify is currently undefined, 
.PN catopen
or
.PN setlocale
substitutes a null string.  Neither function includes the underscore
(_) or period (.) separator in 
.PN %t 
or 
.PN %c
substitutions.
.PP
You can specify more than one pathname when you define these
environment variables.  You separate each pathname from the one that
follows it using a colon (:).  If you need to specify the current
directory in a pathname other than the first pathname in the list, use
a double colon (::).  The functions interpret the first colon as a
separator between pathnames and the second colon as specifying the
current directory.
.PP
The following describes the ICONV, INTLINFO, and NLSPATH environment
variables:
.IP ICONV 10
The ICONV environment variable stores the directory pathname for the conversion 
codesets used by the 
.PN iconv
command. If this variable is undefined, 
.PN iconv
searches the 
.PN /usr/lib/intln/conv
directory.  
.IP
The following example shows how to define ICONV:
.EX
ICONV=/usr/lib/international/conversions
.EE
In this example, 
.PN ICONV
is defined as the directory pathname
.PN /usr/users/international/conversions .
.IP INTLINFO
The INTLINFO environment variable stores the location of the language
database. The
.PN setlocale
function reads INTLINFO when it searches for the database.  
.IP
The following example shows how to define INTLINFO:
.EX
INTLINFO = ":%L:/usr/lib/intln/%L:/usr/lib/intln/ENG_%t.%c"
.EE
In this example, the
.PN setlocale
function searches for the language database named in the LANG environment
variable. The function searches for the variable in the current
directory. If the database is not in the current directory, 
.PN setlocale
searches in the
.PN /usr/lib/intln
directory for that same database. Finally, if the database specified
by LANG is unavailable, 
.PN setlocale
searches in
.PN /usr/lib/intln
for the English language database that matches the current territory
and codeset.
.IP NLSPATH
The NLSPATH environment variable controls where the
.PN catopen 
function searches for a message catalog.
.IP
The following example shows defines NLSPATH:
.EX
NLSPATH=":%N.cat:/nlslib/%N.cat:nlslib/program.cat"
.EE
This definition causes
.PN catopen
to search in the current directory for the message catalog named in the 
.I name
argument you pass.  If the function cannot find the
message catalog in the current directory, it searches in the
.PN /nlslib
directory.  If the catalog is not in that directory, 
.PN catopen
opens the 
.PN /nlslib/program.cat
message catalog.
.SH See Also 
exec(2), catopen(3int), intro(3int), setlocale(3), lang(5int)
.br
.I Guide to Developing International Software