4.3BSD-UWisc/man/cat7/environ.7
ENVIRON(7) UNIX Programmer's Manual ENVIRON(7)
NAME
environ - user environment
SYNOPSIS
extern char **environ;
DESCRIPTION
An array of strings called the `environment' is made avail-
able by _e_x_e_c_v_e(2) when a process begins. By convention
these strings have the form `_n_a_m_e=_v_a_l_u_e'. The following
names are used by various commands:
PATH The sequence of directory prefixes that _s_h, _t_i_m_e,
_n_i_c_e(1), etc., apply in searching for a file known
by an incomplete path name. The prefixes are
separated by `:'. _L_o_g_i_n(1) sets
PATH=:/usr/ucb:/bin:/usr/bin.
HOME A user's login directory, set by _l_o_g_i_n(1) from the
password file _p_a_s_s_w_d(5).
TERM The kind of terminal for which output is to be
prepared. This information is used by commands,
such as _n_r_o_f_f or _p_l_o_t(1G), which may exploit special
terminal capabilities. See /_e_t_c/_t_e_r_m_c_a_p
(_t_e_r_m_c_a_p(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
_t_e_r_m_c_a_p(5),_t_e_r_m_c_a_p(3X).
EXINIT A startup list of commands read by _e_x(1), _e_d_i_t(1),
and _v_i(1).
USER The login name of the user.
PRINTER The name of the default printer to be used by
_l_p_r(1), _l_p_q(1), and _l_p_r_m(1).
Further names may be placed in the environment by the _e_x_p_o_r_t
command and `name=value' arguments in _s_h(1), or by the
_s_e_t_e_n_v command if you use _c_s_h(1). Arguments may also be
placed in the environment at the point of an _e_x_e_c_v_e(2). It
is unwise to conflict with certain _s_h(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)
Printed 12/27/86 May 20, 1985 1