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 programs. The following environmental variables can be used by applications and are expected to 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 localization information that allows users to work with different national conventions. The setlocale(3C) function looks for 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(LC_CTYPE, ""), setlocale() will query the LC_CTYPE environment variable first to see if it is set and non-null. If LC_CTYPE 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 LC_CTYPE are unset or null, the default C locale will be used to set the LC_CTYPE category.

Most commands will invoke setlocale(LC_ALL, "") 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 with names beginning “LC_” are supported to correspond with each category of setlocale(3C). The values of these and the LANG variable should be the names of directories in /usr/lib/locale in which appropriate data files exist.

LC_COLLATE
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).

LC_CTYPE
This category specifies character classification, character conversion, and widths of multibyte characters. The information corresponding to this category is stored in a database created by the chrtbl(1M) command. The default C locale corresponds to the 7-bit ASCII character set. This environment variable is used by ctype(3C), conv(3C), mbchar(3C), and many commands; for example: cat(1), ed(1), ls(1), and vi(1).

LC_MESSAGES
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 databases are created by the gencat(1M) command. This environment variable is used by catopen(3C) and gettxt(3C).

LC_MONETARY
This category specifies the monetary symbols and delimiters used for a particular locale. The information corresponding to this category is stored in a database created by the montbl(1M) command. This environment variable is used by localeconv(3C).

LC_NUMERIC
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 C locale corresponds to "." as the decimal delimiter and no thousands delimiter. This environment variable is used by localeconv(3C), printf(3C), and strtod(3C).

LC_TIME This category specifies date and time formats. The information corresponding to this category is stored in a database specified in strftime(4). The default C locale 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).

LOGNAME
Set by login(1) to the login name of the current user.

LPDEST Names the printer to which lp(1) requests are sent if no destination is provided on the lp command line.

MSGVERB
Controls which standard format message components fmtmsg selects when messages are displayed to stderr [see fmtmsg(1) and fmtmsg(3C)].

SEV_LEVEL
Define severity levels and associate and print strings with them in standard format error messages [see addseverity(3C), fmtmsg(1), and fmtmsg(3C)].

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.

For example:

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, with 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 value of LC_MESSAGES is used instead of LANG if it is 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.

For example:

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.

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 separated by colons (:). login(1) sets PATH=/usr/bin. (For more detail, see sh(1).)

TERM The kind of terminal for which output is to be prepared. This information is used by commands, such as mm(1) or vi(1), which may exploit special capabilities of that terminal.

TZ Time zone information. The contents of the environment variable named TZ are used by the functions ctime(3C), localtime(3C), strftime(3C), and mktime(3C) to override the default time zone. If the first character of TZ is a colon (:), the remainder of the value is the pathname of a compiled time zone information file (see zic(1)); otherwise TZ has the form:

stdoffset[dst[offset],[start[/time],end[/time]]]

std and dst
Three or more bytes that are the designation for the standard (std) and daylight savings time (dst) time zones. Only std is required, if dst is missing, then daylight savings time does not apply in this locale. Upper- and lower-case letters are allowed. Any characters except a leading colon (:), digits, a comma (,), a minus (−) or a plus (+) 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 following 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 time zone is east of the Prime Meridian; otherwise it is west (which may be indicated 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 happens. Each time field describes when, in current local time, the change is made.

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 d-day in month m” which 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 used for start and end if these optional fields are not given.

The time has the same format as offset except that no leading 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) and ksh(1), by the setenv command in csh(1), or by exec(2). It is unwise to conflict with certain shell variables that are frequently exported by .profile files: MAIL, PS1, PS2, IFS (see profile(4)).

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environ(5)

NAME

DESCRIPTION

SEE ALSO