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ENVIRON(7)	   FreeBSD Miscellaneous Information Manual	    ENVIRON(7)

     environ --	user environment

     extern char **environ;

     An	array of strings, called the environment is made available to each
     process by	execve(2) when a process begins.  By convention	these strings
     have the form name=value, and are referred	to as "environment variables".
     A process can query, update, and delete these strings using the
     getenv(3),	setenv(3), and unsetenv(3) functions, respectively.  The
     shells also provide commands to manipulate	the environment; they are de-
     scribed in	the respective shell manual pages.

     What follows is a list of environment variables typically seen on a UNIX
     system.  It includes only those variables that a user can expect to see
     during their day-to-day use of the	system,	and is far from	complete.  En-
     vironment variables specific to a particular program or library function
     are documented in the ENVIRONMENT section of the appropriate manual page.

     BLOCKSIZE	      The size of the block units used by several disk-related
		      commands,	most notably df(1), du(1) and ls(1).
		      BLOCKSIZE	may be specified in units of a byte by speci-
		      fying a number, in units of a kilobyte by	specifying a
		      number followed by `K' or	`k', in	units of a megabyte by
		      specifying a number followed by `M' or `m', and in units
		      of a gigabyte by specifying a number followed by `G' or
		      `g'.  Sizes less than 512	bytes or greater than a	giga-
		      byte are ignored.	 This variable is processed by the
		      getbsize(3) function.

     COLUMNS	      The user's preferred width in column positions for the
		      terminal.	 Utilities such	as ls(1) and who(1) use	this
		      to format	output into columns.  If unset or empty, util-
		      ities will use an	ioctl(2) call to ask the terminal
		      driver for the width.

     EDITOR	      Default editor name.

     EXINIT	      A	startup	list of	commands read by ex(1) and vi(1).

     HOME	      A	user's login directory,	set by login(1)	from the pass-
		      word file	passwd(5).

     LANG	      This variable configures all programs which use
		      setlocale(3) to use the specified	locale unless the LC_*
		      variables	are set.

     LC_ALL	      Overrides	the values of LC_COLLATE, LC_CTYPE,

     LC_COLLATE	      Locale to	be used	for ordering of	strings.

     LC_CTYPE	      Locale to	be used	for character classification (letter,
		      space, digit, etc.) and for interpreting byte sequences
		      as multibyte characters.

     LC_MESSAGES      Locale to	be used	for diagnostic messages.

     LC_MONETARY      Locale to	be used	for interpreting monetary input	and
		      formatting output.

     LC_NUMERIC	      Locale to	be used	for interpreting numeric input and
		      formatting output.

     LC_TIME	      Locale to	be used	for interpreting dates input and for
		      formatting output.

     MAIL	      The location of the user's mailbox instead of the	de-
		      fault in /var/mail, used by mail(1), sh(1), and many
		      other mail clients.

     MANPATH	      The sequence of directories, separated by	colons,
		      searched by man(1) when looking for manual pages.

     NLSPATH	      List of directories to be	searched for the message cata-
		      log referred to by LC_MESSAGES.  See catopen(3).

     PAGER	      Default paginator	program.  The program specified	by
		      this variable is used by mail(1),	man(1),	ftp(1),	etc,
		      to display information which is longer than the current

     PATH	      The sequence of directories, separated by	colons,
		      searched by csh(1), sh(1), system(3), execvp(3), etc,
		      when looking for an executable file.  PATH is set	to
		      ``/usr/bin:/bin''	initially by login(1).

     POSIXLY_CORRECT  When set to any value, this environment variable modi-
		      fies the behaviour of certain commands to	(mostly) exe-
		      cute in a	strictly POSIX-compliant manner.

     PRINTER	      The name of the default printer to be used by lpr(1),
		      lpq(1), and lprm(1).

     PWD	      The current directory pathname.

     SHELL	      The full pathname	of the user's login shell.

     TERM	      The kind of terminal for which output is to be prepared.
		      This information is used by commands, such as nroff(1)
		      or plot(1) which may exploit special terminal capabili-
		      ties.  See /usr/share/misc/termcap (termcap(5)) for a
		      list of terminal types.

     TERMCAP	      The string describing the	terminal in TERM, or, if it
		      begins with a '/', the name of the termcap file.	See
		      TERMPATH below, and termcap(5).

     TERMPATH	      A	sequence of pathnames of termcap files,	separated by
		      colons or	spaces,	which are searched for terminal	de-
		      scriptions in the	order listed.  Having no TERMPATH is
		      equivalent to a TERMPATH of $HOME/.termcap:/etc/termcap.
		      TERMPATH is ignored if TERMCAP contains a	full pathname.

     TMPDIR	      The directory in which to	store temporary	files.	Most
		      applications use either /tmp or /var/tmp.	 Setting this
		      variable will make them use another directory.

     TZ		      The timezone to use when displaying dates.  The normal
		      format is	a pathname relative to /usr/share/zoneinfo.
		      For example, the command

			    env	TZ=America/Los_Angeles date

		      displays the current time	in California.	See tzset(3)
		      for more information.

     USER	      The login	name of	the user.  It is recommended that por-
		      table applications use LOGNAME instead.

     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).  It is unwise to change certain sh(1) variables that are fre-
     quently exported by .profile files, such as MAIL, PS1, PS2, and IFS, un-
     less you know what	you are	doing.

     The current environment variables can be printed with env(1), set(1) or
     printenv(1) in sh(1) and env(1), printenv(1) or the printenv built-in
     command in	csh(1).

     cd(1), csh(1), env(1), ex(1), login(1), printenv(1), sh(1), execve(2),
     execle(3),	getbsize(3), getenv(3),	setenv(3), setlocale(3), system(3),
     termcap(3), termcap(5)

     The environ manual	page appeared in Version 7 AT&T	UNIX.

FreeBSD	13.0			August 5, 2020			  FreeBSD 13.0


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