environ(5) environ(5)
NAME
environ - user environment
DESCRIPTION
When a process begins execution, exec routines make available an array
of strings called the "environment" [see exec(2)]. By convention,
these strings have the form variable=value, for example,
PATH=/sbin:/usr/sbin. These environmental variables provide a way to
make information about a program's environment available to applica-
tions. The following environmental variables must be set in the target
run-time environment.
HOME The name of the user's login directory, set by login(1)
from the password file [see passwd(4)].
LANG The string used to specify information about the locale,
that allows users to work with different national conven-
tions. The setlocale(3C) function uses the LANG environment
variable when it is called with "" as the locale argument.
LANG is used as the default locale if the corresponding
environment variable for a particular category is unset.
For example, when setlocale is invoked as
setlocale(LCCTYPE, "")
the LCCTYPE environment variable is checked first, to see
if it is set and non-null. If LCCTYPE is not set or null,
then setlocale will check the LANG environment variable to
see if it is set and non-null. If both LANG and LCCTYPE
are unset or null, the default C locale will be used to set
the LCCTYPE category. Most commands will invoke
setlocale(LCALL, "")
prior to any other processing. This allows the command to
be used with different national conventions by setting the
appropriate environment variables.
The following environment variables are supported to corre-
spond with each category of setlocale(3C):
LCCOLLATE
This category specifies the collation sequence being
used. The information corresponding to this category
is stored in a database created by the colltbl(1M)
command. This environment variable affects strcoll(3C)
and strxfrm(3C).
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LCCTYPE
This category specifies character classification,
character conversion, and widths of multibyte charac-
ters. The database created by the chrtbl(1M) command.
The default for C corresponds to the 7-bit character
set. This environment variable is used by ctype(3C),
mbchar(3C), and many commands; for example: cat(1),
ed(1), ls(1), and vi(1).
LCMESSAGES
This category specifies the language of the message
database being used. For example, an application may
have one message database with French messages, and
another database with German messages. Message data-
bases are created by the mkmsgs(1) command. This envi-
ronment variable is used by exstr(1), gettxt(1),
gettxt(3C), and srchtxt(1).
LCMONETARY
Used for a particular locale. The information corre-
sponding to this category is stored in a database
created by the montbl(1M) command. This environment
variable is used by localeconv(3C).
LCNUMERIC
This category specifies the decimal and thousands
delimiters. The information corresponding to this
category is stored in a database created by the
chrtbl(1M) command. The default for C corresponds to .
as the decimal delimiter and no thousands delimiter.
This environment variable is used by localeconv(3C),
printf(3S), and strtod(3C).
LCTIME
This category specifies date and time formats. The
information corresponding to this category is stored
in a database specified in LCTIME(4). The default for
C corresponds to U.S. date and time formats. This
environment variable is used by many commands and
functions; for example: at(1), calendar(1), date(1),
strftime(3C), and getdate(3C).
MSGVERB Controls which standard format message components fmtmsg
selects when messages are displayed to stderr [see
fmtmsg(1) and fmtmsg(3C)].
SEVLEVEL Defines severity levels and associates and prints strings
with them in standard format error messages [see
addseverity(3C), fmtmsg(1), and fmtmsg(3C)].
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NETPATH A colon-separated list of network identifiers. A network
identifier is a character string used by the Network Selec-
tion component of the system to provide application-speci-
fic default network search paths. A network identifier must
consist of non-NULL characters and must have a length of at
least 1. No maximum length is specified. Network identif-
iers are normally chosen by the superuser. A network iden-
tifier is also the first field in any /etc/netconfig file
entry. NETPATH thus provides a link into the /etc/netconfig
file and the information about a network contained in that
network's entry. /etc/netconfig is maintained by the
superuser. The library routines described in getnetpath(3N)
access the NETPATH environment variable.
NLSPATH Contains a sequence of templates which catopen(3C) uses
when attempting to locate message catalogs. Each template
consists of an optional prefix, one or more substitution
fields, a filename and an optional suffix.
NLSPATH="/system/nlslib/%N.cat"
defines that catopen should look for all message catalogs
in the directory /system/nlslib, where the catalog name
should be constructed from the name parameter passed to
catopen(), %N, plus the suffix .cat.
Substitution fields consist of a % symbol, followed by a
single-letter keyword. The following keywords are currently
defined:
%N The value of the name parameter passed to catopen().
%L The value of LANG.
%l The language element from LANG.
%t The territory element from LANG.
%c The codeset element from LANG.
%% A single % character.
An empty string is substituted if the specified value is
not currently defined. The separators and . are not
included in %t and %c substitutions.
Templates defined in NLSPATH are separated by colons. A
leading colon or two adjacent colons :: is equivalent to
specifying %N.
NLSPATH=":%N.cat:/nlslib/%L/%N.cat"
indicates to catopen that it should look for the requested
message catalog in name, name.cat and
/nlslib/$LANG/name.cat.
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PATH The sequence of directory prefixes that sh(1), time(1),
nice(1), nohup(1), etc., apply in searching for a file
known by an incomplete path name. The prefixes are sepa-
rated by colons. login(1) sets PATH=/usr/bin [see sh(1)].
TERM The kind of terminal for which output is to be prepared.
This information is used by commands, such as vi(1), which
may exploit special capabilities of that terminal.
TZ Time zone information. The contents of this environment
variable are used by the functions ctime(3C), localtime
[see ctime(3C)], strftime(3C) and mktime(3C) to override
the default timezone. If the first character of TZ is a
colon, the behavior is implementation defined, otherwise TZ
has the form:
std offset [dst [offset],[start[/time],end[/time]]]
std and dst contain three or more bytes that are the desig-
nation for the standard (std) and daylight savings time
(dst) timezones. Only std is required. If dst is missing,
then daylight savings time does not apply in this environ-
ment. Upper- and lower-case letters are allowed. Any char-
acters except a leading colon, digits, a comma, a minus
sign or a plus sign are allowed.
offset indicates the value one must add to the local time
to arrive at Coordinated Universal Time.
The offset has the form:
hh [:mm [:ss]]
The minutes (mm) and seconds (ss) are optional. The hour
(hh) is required and may be a single digit. The offset fol-
lowing std is required. If no offset follows dst, daylight
savings time is assumed to be one hour ahead of standard
time. One or more digits may be used; the value is always
interpreted as a decimal number. The hour must be between 0
and 24, and the minutes (and seconds) if present between 0
and 59. Out of range values may cause unpredictable
behavior. If preceded by a -, the timezone is east of the
Prime Meridian; otherwise it is west (which may be indi-
cated by an optional preceding + sign).
start/time, end/time indicates when to change to and back
from daylight savings time, where start/time describes when
the change from standard time to daylight savings time
occurs, and end/time describes when the change back hap-
pens. Each time field specifies when the change is made.
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The formats of start and end are one of the following:
Jn The Julian day n (1 <= n <= 365). Leap days are not
counted. That is, in all years, February 28 is day
59 and March 1 is day 60. It is impossible to refer
to the occasional February 29.
n The zero-based Julian day (0 <= n <= 365); leap
days are counted, and it is possible to refer to
February 29.
Mm.n.d The dth day, (0 <= d <= 6) of week n of month m of
the year (1 <= n <= 5, 1 <= m <= 12), where week 5
means "the last day number d in month m", and may
occur in either the fourth or the fifth week. Week
1 is the first week in which the dth day occurs.
Day zero is Sunday.
Implementation specific defaults are assumed for start and
end if these optional fields are not given.
The time has the same format as offset except that no lead-
ing sign (- or +) is allowed. The default if time is not
given is 02:00:00.
Further names may be placed in the environment by the export command
and name=value arguments in sh(1), or by exec(2). It is unwise to con-
flict with certain shell variables that are frequently exported by
.profile files: MAIL, PS1, PS2, IFS [see profile(4)].
SEE ALSO
cat(1), date(1), ed(1), fmtmsg(1), login(1), ls(1), mkmsgs(1),
nice(1), nohup(1), sh(1), sort(1), time(1), vi(1), chrtbl(1M),
colltbl(1M), montbl(1M), exec(2), addseverity(3C), catopen(3C),
ctime(3C), ctype(3C), fmtmsg(3C), getdate(3C), gettxt(3C),
localeconv(3C), mbchar(3C), mktime(3C), strcoll(3C), strftime(3C),
strtod(3C), strxfrm(3C), getnetpath(3N), printf(3S), LCTIME(4),
netconfig(4), passwd(4), profile(4), timezone(4).
Manual "Programmers Guide: Internationalization - Localization".
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