1.\" Copyright (c) 1983, 1990, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)environ.7 8.3 (Berkeley) 4/19/94 33.\" $FreeBSD$ 34.\" 35.Dd April 12, 2003 36.Dt ENVIRON 7 37.Os 38.Sh NAME 39.Nm environ 40.Nd user environment 41.Sh SYNOPSIS 42.Ar extern char **environ ; 43.Sh DESCRIPTION 44An array of strings called the 45.Ar environment 46is made available by 47.Xr execve 2 48when a process begins. 49By convention these strings have the form 50.Dq Ar name=value . 51The following names are used by various commands: 52.Bl -tag -width LC_MONETARY 53.It Ev BLOCKSIZE 54The size of the block units used by several commands, most notably 55.Xr df 1 , 56.Xr du 1 57and 58.Xr ls 1 . 59This variable is processed by the 60.Xr getbsize 3 61function. 62.It Ev COLUMNS 63The user's preferred width in column positions for the terminal. 64Utilities such as 65.Xr ls 1 66and 67.Xr who 1 68use this to format output into columns. 69If unset or empty, utilities will use an 70.Xr ioctl 2 71call to ask the terminal driver for the width. 72.It Ev EDITOR 73Default editor name. 74.It Ev EXINIT 75A startup list of commands read by 76.Xr ex 1 77and 78.Xr vi 1 . 79.It Ev HOME 80A user's login directory, set by 81.Xr login 1 82from the password file 83.Xr passwd 5 . 84.It Ev LANG 85This variable configures all programs which use 86.Xr setlocale 3 87to use the specified locale unless the 88.Ev LC_* 89variables are set. 90.It Ev LC_ALL 91Overrides the values of 92.Ev LC_COLLATE , 93.Ev LC_CTYPE , 94.Ev LC_MESSAGES , 95.Ev LC_MONETARY , 96.Ev LC_NUMERIC , 97.Ev LC_TIME 98and 99.Ev LANG . 100.It Ev LC_COLLATE 101Locale to be used for ordering of strings. 102.It Ev LC_CTYPE 103Locale to be used for character classification 104(letter, space, digit, etc.) and for interpreting byte sequences as 105multibyte characters. 106.It Ev LC_MESSAGES 107Locale to be used for diagnostic messages. 108.It Ev LC_MONETARY 109Locale to be used for interpreting monetary input 110and formatting output. 111.It Ev LC_NUMERIC 112Locale to be used for interpreting numeric input and 113formatting output. 114.It Ev LC_TIME 115Locale to be used for interpreting dates input and 116for formatting output. 117.It Ev MAIL 118The location of the user's 119mailbox instead of the default in /var/mail, 120used by 121.Xr mail 1 , 122.Xr sh 1 , 123and many other mail clients. 124.It Ev NLSPATH 125List of directories to be searched for the message catalog referred to by 126.Ev LC_MESSAGES . 127See 128.Xr catopen 3 . 129.It Ev PAGER 130Default paginator program. 131The program specified by this variable is used by 132.Xr mail 1 , 133.Xr man 1 , 134.Xr ftp 1 , 135etc, to display information which is longer than the current display. 136.It Ev PATH 137The sequence of directories, separated by colons, searched by 138.Xr csh 1 , 139.Xr sh 1 , 140.Xr system 3 , 141.Xr execvp 3 , 142etc, when looking for an executable file. 143.Ev PATH 144is set to ``/usr/bin:/bin'' initially by 145.Xr login 1 . 146.It Ev PRINTER 147The name of the default printer to be used by 148.Xr lpr 1 , 149.Xr lpq 1 , 150and 151.Xr lprm 1 . 152.It Ev PWD 153The current directory pathname. 154.It Ev SHELL 155The full pathname of the user's login shell. 156.It Ev TERM 157The kind of terminal for which output is to be prepared. 158This information is used by commands, such as 159.Xr nroff 1 160or 161.Xr plot 1 162which may exploit special terminal capabilities. 163See 164.Pa /usr/share/misc/termcap 165.Pq Xr termcap 5 166for a list of terminal types. 167.It Ev TERMCAP 168The string describing the terminal in 169.Ev TERM , 170or, if 171it begins with a '/', the name of the termcap file. 172See 173.Ev TERMPATH 174below, and 175.Xr termcap 5 . 176.It Ev TERMPATH 177A sequence of pathnames of termcap files, separated by colons or spaces, 178which are searched for terminal descriptions in the order listed. 179Having 180no 181.Ev TERMPATH 182is equivalent to a 183.Ev TERMPATH 184of 185.Dq Pa $HOME/.termcap:/etc/termcap . 186.Ev TERMPATH 187is ignored if 188.Ev TERMCAP 189contains a full pathname. 190.It Ev TMPDIR 191The directory in which to store temporary files. 192Most applications use either 193.Dq /tmp 194or 195.Dq /var/tmp . 196Setting this variable will make them use another directory. 197.It Ev TZ 198The timezone to use when displaying dates. 199The normal format is a pathname relative to 200.Dq Pa /usr/share/zoneinfo . 201For example, the command 202.Dq env TZ=America/Los_Angeles date 203displays the current time in California. 204See 205.Xr tzset 3 206for more information. 207.It Ev USER 208The login name of the user. 209.El 210.Pp 211Further names may be placed in the environment by the 212.Ic export 213command and 214.Ar name=value 215arguments in 216.Xr sh 1 , 217or by the 218.Ic setenv 219command if you use 220.Xr csh 1 . 221It is unwise to change certain 222.Xr sh 1 223variables that are frequently exported by 224.Pa .profile 225files, such as 226.Ev MAIL , 227.Ev PS1 , 228.Ev PS2 , 229and 230.Ev IFS , 231unless you know what you are doing. 232.Pp 233The current environment variables can be printed with 234.Xr env 1 , 235.Xr set 1 236or 237.Xr printenv 1 238in 239.Xr sh 1 240and 241.Xr env 1 , 242.Xr printenv 1 243or the 244.Cm printenv 245built-in command in 246.Xr csh 1 . 247.Sh SEE ALSO 248.Xr cd 1 , 249.Xr csh 1 , 250.Xr env 1 , 251.Xr ex 1 , 252.Xr login 1 , 253.Xr printenv 1 , 254.Xr sh 1 , 255.Xr execve 2 , 256.Xr execle 3 , 257.Xr getenv 3 , 258.Xr getbsize 3 , 259.Xr setenv 3 , 260.Xr setlocale 3 , 261.Xr system 3 , 262.Xr termcap 3 , 263.Xr termcap 5 264.Sh HISTORY 265The 266.Nm 267manual page appeared in 268.Bx 4.2 . 269