environ - user environment
extern char **environ;
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 search-
ing 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 capa-
bilities. 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
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,
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)