4.3BSD - /usr/man/cat7/environ.0

ENVIRON(7)                                                          ENVIRON(7)


NAME
       environ - user environment

SYNOPSIS
       extern char **environ;

DESCRIPTION
       An  array  of  strings  called  the  ‘environment’ is made available by
       execve(2) when a process begins.  By convention these strings have  the
       form ‘name=value’.  The following names are used by various commands:

       PATH    The  sequence  of  directory  prefixes  that sh, time, nice(1),
               etc., apply in searching for a file known by an incomplete path
               name.   The  prefixes  are  separated  by  ‘:’.   Login(1) sets
               PATH=:/usr/ucb:/bin:/usr/bin.

       HOME    A user’s login directory, set by  login(1)  from  the  password
               file passwd(5).

       TERM    The  kind of terminal for which output is to be prepared.  This
               information is used by commands, such  as  nroff  or  plot(1G),
               which   may   exploit   special   terminal  capabilities.   See
               /etc/termcap (termcap(5)) for a list of terminal types.

       SHELL   The file name of the users login shell.

       TERMCAP The string describing the terminal in TERM, or the name of  the
               termcap file, see termcap(5),termcap(3X).

       EXINIT  A startup list of commands read by ex(1), edit(1), and vi(1).

       USER    The login name of the user.

       PRINTER The  name  of the default printer to be used by lpr(1), lpq(1),
               and lprm(1).

       Further names may be placed in the environment by  the  export  command
       and  ‘name=value’  arguments  in sh(1), or by the setenv command if you
       use csh(1).  Arguments may also be placed in  the  environment  at  the
       point  of  an  execve(2).   It is unwise to conflict with certain sh(1)
       variables that are frequently exported by ‘.profile’ files: MAIL,  PS1,
       PS2, IFS.

SEE ALSO
       csh(1),  ex(1),  login(1),  sh(1),  execve(2),  system(3), termcap(3X),
       termcap(5)


4.2 Berkeley Distribution        May 20, 1985                       ENVIRON(7)