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environ(5)            Standards, Environments, and Macros           environ(5)

       environ - user environment

       When  a  process  begins execution, one of the exec family of functions
       makes 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 pro-

       A name may be placed in the  environment  by  the  export  command  and
       name=value  arguments  in sh(1), or by one of the exec functions. It is
       unwise to conflict with certain shell variables such as MAIL, PS1, PS2,
       and IFS that are frequently exported by .profile files; see profile(4).

       The  following  environmental variables can be used by applications and
       are expected to be set in the target run-time environment.


           The name of the user's login directory, set by  login(1)  from  the
           password file; see passwd(4).


           The  string  used  to specify internationalization information that
           allows users to work with different national conventions. The  set-
           locale(3C) function checks 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 or null. If, however,  LC_ALL is set to a  valid,
           non-empty  value,  its  contents are used to override both the LANG
           and the other LC_* variables. For example, when invoked  as  setlo-
           cale(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 vari-
           able 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  vari-

           The  following environment variables correspond to each category of


               If set to a valid, non-empty string value, override the  values
               of LANG and all the other LC_*variables.


               This  category specifies the character collation sequence being
               used.  The information corresponding to this category is stored
               in  a  database   created  by  the localedef(1) command.   This
               environment variable affects strcoll(3C) and strxfrm(3C).


               This category  specifies  character  classification,  character
               conversion,  and  widths of multibyte characters. When LC_CTYPE
               is set to a valid value, the calling utility  can  display  and
               handle text and file names containing valid characters for that
               locale;   Extended Unix Code (EUC) characters where  any  indi-
               vidual  character can be 1, 2, or 3 bytes wide; and EUC charac-
               ters of 1, 2, or 3 column widths. The default "C" locale corre-
               sponds  to  the 7-bit ASCII character set; only characters from
               ISO 8859-1 are valid. The  information  corresponding  to  this
               category  is  stored  in  a database created by the localedef()
               command.  This  environment  variable  is  used  by  ctype(3C),
               mblen(3C), and many commands, such as cat(1), ed(1), ls(1), and


               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 mkmsgs(1) com-
               mand. This environment variable is used by exstr(1), gettxt(1),
               srchtxt(1), gettxt(3C), and gettext(3C).


               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
               localedef(1) command. This  environment  variable  is  used  by


               This  category  specifies the decimal and thousands delimiters.
               The information corresponding to this category is stored  in  a
               database   created  by  the  localedef() command. The default C
               locale corresponds to "." as the decimal delimiter and no thou-
               sands  delimiter.  This environment variable is used by locale-
               conv(3C), printf(3C), and strtod(3C).


               This category specifies date and time formats. The  information
               corresponding  to  this category is stored in a database speci-
               fied in localedef(). 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).


           Controls  which  standard  format message components fmtmsg selects
           when  messages  are  displayed  to  stderr;  see    fmtmsg(1)   and


           A colon-separated list of network identifiers. A network identifier
           is a character string used by the Network  Selection  component  of
           the  system  to provide application-specific 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 identifiers are normally chosen by the  system  administra-
           tor.  A network identifier is also the first field in any /etc/net-
           config file entry. NETPATH thus provides a link into the  /etc/net-
           config  file  and the information about a network contained in that
           network's entry. /etc/netconfig is maintained by the system  admin-
           istrator. The library routines described in getnetpath(3NSL) access
           the NETPATH environment variable.


           Contains a sequence of templates which catopen(3C) and  gettext(3C)
           use  when attempting to locate message catalogs. Each template con-
           sists of an optional prefix, one or  more  substitution  fields,  a
           filename and an optional suffix. For example:


           defines  that catopen() should look for all message catalogs in the
           directory /system/nlslib, where the catalog  name  should  be  con-
           structed  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 or LC_MESSAGES.

           %l       The language element from LANG or LC_MESSAGES.

           %t       The territory element from LANG or LC_MESSAGES.

           %c       The codeset element from LANG or LC_MESSAGES.

           %%       A single % character.

           An  empty  string is substituted if the specified value is not cur-
           rently 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:


           indicates  to  catopen() that it should look for the requested mes-
           sage catalog in name, name.cat and /nlslib/$LANG/name.cat. For get-
           text(), %N automatically maps to "messages".

           If  NLSPATH  is unset or NULL, catopen() and gettext() call  setlo-
           cale(3C), which checks LANG and the  LC_* variables to  locate  the
           message catalogs.

           NLSPATH  will  normally  be  set  up  on  a  system  wide basis (in
           /etc/profile) and thus makes the location  and  naming  conventions
           associated  with  message catalogs transparent to both programs and


           The sequence of directory prefixes that  sh(1),  time(1),  nice(1),
           nohup(1),  and  other utilities 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).


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


           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.


           Timezone information. The contents of this environment variable are
           used by the functions ctime(3C), localtime(3C),  strftime(3C),  and
           mktime(3C)  to  override  the default timezone. The value of TZ has
           one of the two formats (spaces inserted for clarity):



           std offset dst offset, rule

           If TZ is of the first format (that is, if the first character is  a
           colon  (:)),  or  if TZ is not of the second format, then TZ desig-
           nates  a  path  to   a   timezone   database   file   relative   to
           /usr/share/lib/zoneinfo/, ignoring a leading colon if one exists.

           Otherwise, TZ is of the second form, which when expanded is as fol-


           std and dst             Indicate no less than three, nor more  than
                                   {TZNAME_MAX},  bytes  that are the designa-
                                   tion for the standard (std) or the alterna-
                                   tive  (dst,  such as Daylight Savings Time)
                                   timezone. Only std is required; if  dst  is
                                   missing, then the alternative time does not
                                   apply  in  this  timezone.  Each  of  these
                                   fields  can occur in either of two formats,
                                   quoted or unquoted:

                                     o  In the quoted form, the first  charac-
                                        ter  is  the less-than ('<') character
                                        and the last character is the greater-
                                        than  ('>')  character. All characters
                                        between these quoting  characters  are
                                        alphanumeric  characters from the por-
                                        table character  set  in  the  current
                                        locale, the plus-sign ('+') character,
                                        or the minus-sign ('-') character. The
                                        std and dst fields in this case do not
                                        include the quoting characters.

                                     o  In the unquoted form,  all  characters
                                        in these fields are alphabetic charac-
                                        ters from the portable  character  set
                                        in the current locale.

                                   The   interpretation  of  these  fields  is
                                   unspecified if either field  is  less  than
                                   three  bytes  (except for the case when dst
                                   is missing), more than {TZNAME_MAX}  bytes,
                                   or  if  they  contain characters other than
                                   those specified.

           offset                  Indicate the value  one  must  add  to  the
                                   local time to arrive at Coordinated Univer-
                                   sal Time. The offset has the form:


                                   The  minutes  (mm)  and  seconds  (ss)  are
                                   optional. The hour (hh) is required and can
                                   be a single digit. The offset following std
                                   is required. If no offset follows dst, day-
                                   light savings time is  assumed  to  be  one
                                   hour  ahead  of  standard time. One or more
                                   digits can 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, must be between
                                   0 and 59. Out of  range  values  can  cause
                                   unpredictable  behavior.  If  preceded by a
                                   "-", the timezone  is  east  of  the  Prime
                                   Meridian.  Otherwise,  it  is  west  of the
                                   Prime Meridian (which can be  indicated  by
                                   an optional preceding "+" sign).

           start/time,end/time     Indicate  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
                                   occurs.  Each time field describes when, in
                                   current local time, the change is made.

                                   The formats of start and end are one of the

                                   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 d**th 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  d**th day occurs. Day zero is

                                   Implementation specific defaults  are  used
                                   for  start and end if these optional fields
                                   are not specified.

                                   The time has  the  same  format  as  offset
                                   except  that  no leading sign ("-" or "+" )
                                   is allowed. If time is not  specified,  the
                                   default value is 02:00:00.

       cat(1),  date(1),  ed(1),  fmtmsg(1),  localedef(1),  login(1),  ls(1),
       mkmsgs(1), nice(1), nohup(1), sh(1), sort(1), time(1), vi(1),  exec(2),
       addseverity(3C),  catopen(3C),  ctime(3C),  ctype(3C), fmtmsg(3C), get-
       date(3C), getnetpath(3NSL),  gettext(3C),  gettxt(3C),  localeconv(3C),
       mblen(3C),  mktime(3C),  printf(3C),  setlocale(3C), strcoll(3C), strf-
       time(3C),   strtod(3C),   strxfrm(3C),    TIMEZONE(4),    netconfig(4),
       passwd(4), profile(4)

SunOS 5.10                        19 Nov 2002                       environ(5)