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31 .\" @(#)environ.7 8.3 (Berkeley) 4/19/94
33 .Dd $Mdocdate: October 28 2010 $
40 .Ar extern char **environ ;
42 An array of strings called the
46 when a process begins.
47 By convention these strings have the form
48 .Ar name Ns = Ns Ar value .
49 The following variables are recognized by various commands:
50 .Bl -tag -width BLOCKSIZE
52 The size of the block units used by several commands, most notably
57 May be specified in units of a byte by specifying a number,
58 in units of a kilobyte by specifying a number followed by
62 in units of a megabyte by specifying a number followed by
66 or in units of a gigabyte by specifying a number followed
71 Sizes less than 512 bytes or greater than a gigabyte are ignored.
73 A list of startup commands read by
78 The user's login directory, set by
80 from the password file
83 The login name of the user.
85 The sequence of directories, separated by colons, searched by
91 etc. when looking for an executable file.
92 Initially set to the value of
98 but expanded to include
107 The name of the default printer to be used by
113 The current working directory.
115 The full pathname of the user's login shell.
117 The kind of terminal for which output is to be prepared.
118 This information is used by commands such as
120 which may exploit special terminal capabilities.
122 .Pa /usr/share/misc/termcap
124 for a list of terminal types.
126 The string describing the terminal in
128 or, if it begins with a
130 the name of the termcap file.
138 A sequence of pathnames of termcap files, separated by colons or spaces,
139 which are searched for terminal descriptions in the order listed.
145 .Pa $HOME/.termcap:/etc/termcap .
149 contains a full pathname.
151 The directory in which to store temporary files.
152 Most applications use either
156 Setting this variable will make them use another directory.
158 The time zone to use when displaying dates.
159 The normal format is a pathname relative to
160 .Pa /usr/share/zoneinfo .
161 For example, the command
162 .Ic env TZ=US/Pacific date
163 displays the current time in California.
166 for more information.
168 Deprecated synonym of
170 (for backwards compatibility).
173 Further names may be placed in the environment by the
176 .Ar name Ns = Ns Ar value
183 It is unwise to change certain
185 variables that are frequently exported by
193 unless you know what you are doing.
195 The current environment variables can be printed with
216 manual page appeared in