[unix-history] / .ref-BSD-3 / usr / man / man5 / environ.5

.TH ENVIRON 5 11/16/79 5
.UC
.SH NAME
environ \- user environment
.SH SYNOPSIS
.B extern char **environ;
.SH DESCRIPTION
An array of strings called the `environment' is
made available by
.IR exec (2)
when a process begins.
By convention these strings have the form
`name=value'.
The following names are used by various commands:
.TP
PATH
The sequence of directory prefixes that
.I sh, time,
.IR nice (1),
etc.,
apply in searching for a file known by an incomplete path name.
The prefixes are separated by `:'.
.IR Login (1)
sets PATH=:/bin:/usr/bin.
.TP
HOME
A user's login directory, set by
.IR login (1)
from the password file
.IR passwd (5).
.TP
TERM
The kind of terminal for which output is to be prepared.
This information is used by commands, such as
.I nroff
or
.IR plot (1),
which may exploit special terminal capabilities.
See
.I /etc/termcap
.RI ( termcap (5))
for a list of terminal types.
.TP
SHELL
The file name of the users login shell.
.TP
TERMCAP
The string describing the terminal in TERM,
or the name of the termcap file, see
.IR termcap (5), termlib (3).
.TP
EXINIT
A startup list of commands read by
.IR ex (1),
.IR edit (1),
and
.IR vi (1).
.PP
Further names may be placed in the environment by
the
.I export
command and `name=value' arguments in
.IR sh (1),
or by the
.I setenv
command if you use
.IR csh (1).
Arguments may also be placed in the environment at the point of an
.IR exec (2).
It is unwise to conflict with
certain 
.IR sh (1)
variables that are frequently exported by
`.profile' files:
MAIL, PS1, PS2, IFS.
.SH SEE ALSO
csh(1), ex(1), login(1), sh(1), exec(2), system(3), termlib(3), termcap(5), term(7)
Commit	Line	Data
e4be1df6 BJ	1	.TH ENVIRON 5 11/16/79 5
	2	.UC
	3	.SH NAME
	4	environ \- user environment
	5	.SH SYNOPSIS
	6	.B extern char **environ;
	7	.SH DESCRIPTION
	8	An array of strings called the `environment' is
	9	made available by
	10	.IR exec (2)
	11	when a process begins.
	12	By convention these strings have the form
	13	`name=value'.
	14	The following names are used by various commands:
	15	.TP
	16	PATH
	17	The sequence of directory prefixes that
	18	.I sh, time,
	19	.IR nice (1),
	20	etc.,
	21	apply in searching for a file known by an incomplete path name.
	22	The prefixes are separated by `:'.
	23	.IR Login (1)
	24	sets PATH=:/bin:/usr/bin.
	25	.TP
	26	HOME
	27	A user's login directory, set by
	28	.IR login (1)
	29	from the password file
	30	.IR passwd (5).
	31	.TP
	32	TERM
	33	The kind of terminal for which output is to be prepared.
	34	This information is used by commands, such as
	35	.I nroff
	36	or
	37	.IR plot (1),
	38	which may exploit special terminal capabilities.
	39	See
	40	.I /etc/termcap
	41	.RI ( termcap (5))
	42	for a list of terminal types.
	43	.TP
	44	SHELL
	45	The file name of the users login shell.
	46	.TP
	47	TERMCAP
	48	The string describing the terminal in TERM,
	49	or the name of the termcap file, see
	50	.IR termcap (5), termlib (3).
	51	.TP
	52	EXINIT
	53	A startup list of commands read by
	54	.IR ex (1),
	55	.IR edit (1),
	56	and
	57	.IR vi (1).
	58	.PP
	59	Further names may be placed in the environment by
	60	the
	61	.I export
	62	command and `name=value' arguments in
	63	.IR sh (1),
	64	or by the
65	.I setenv
66	command if you use
67	.IR csh (1).
68	Arguments may also be placed in the environment at the point of an
69	.IR exec (2).
70	It is unwise to conflict with
71	certain
72	.IR sh (1)
73	variables that are frequently exported by
74	`.profile' files:
75	MAIL, PS1, PS2, IFS.
76	.SH SEE ALSO
77	csh(1), ex(1), login(1), sh(1), exec(2), system(3), termlib(3), termcap(5), term(7)