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.\" Copyright (c) 1993 Michael Haardt (michael@moria.de),
.\" Fri Apr 2 11:32:09 MET DST 1993
.\" and Andries Brouwer (aeb@cwi.nl), Fri Feb 14 21:47:50 1997.
.\"
getent.1, _syscall.2, acct.2, adjtimex.2, bdflush.2, brk.2, cacheflush.2, getsid.2, getxattr.2, inotify_add_watch.2, inotify_init.2, inotify_rm_watch.2, ioperm.2, ipc.2, listxattr.2, mlock.2, modify_ldt.2, mremap.2, nanosleep.2, outb.2, perf_event_open.2, ptrace.2, removexattr.2, s390_runtime_instr.2, sched_get_priority_max.2, sched_rr_get_interval.2, sched_setaffinity.2, sched_setparam.2, sched_setscheduler.2, sched_yield.2, setsid.2, setxattr.2, socketcall.2, unimplemented.2, aio_cancel.3, aio_error.3, aio_fsync.3, aio_read.3, aio_return.3, aio_suspend.3, aio_write.3, cfree.3, crypt.3, dlopen.3, encrypt.3, errno.3, fenv.3, ftime.3, ftw.3, getgrent_r.3, getpass.3, getpwent_r.3, getutent.3, hsearch.3, lio_listio.3, lockf.3, login.3, longjmp.3, perror.3, printf.3, scandirat.3, setjmp.3, strfmon.3, strtoimax.3, termios.3, ttyname.3, ualarm.3, updwtmp.3, wcstoimax.3, wordexp.3, console_ioctl.4, dsp56k.4, fd.4, hd.4, intro.4, lp.4, mem.4, null.4, ram.4, rtc.4, sk98lin.4, tty.4, ttyS.4, vcs.4, filesystems.5, group.5, host.conf.5, hosts.5, intro.5, issue.5, motd.5, networks.5, nologin.5, nsswitch.conf.5, passwd.5, proc.5, protocols.5, securetty.5, shells.5, termcap.5, ttytype.5, utmp.5, intro.6, armscii-8.7, ascii.7, bootparam.7, cp1251.7, environ.7, glob.7, intro.7, iso_8859-1.7, iso_8859-10.7, iso_8859-11.7, iso_8859-13.7, iso_8859-14.7, iso_8859-15.7, iso_8859-16.7, iso_8859-2.7, iso_8859-3.7, iso_8859-4.7, iso_8859-5.7, iso_8859-6.7, iso_8859-7.7, iso_8859-8.7, iso_8859-9.7, koi8-r.7, koi8-u.7, posixoptions.7, standards.7, unicode.7, utf-8.7, intro.8: s/GPLv2+_doc_full/GPLv2+_DOC_FULL/ Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
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.\" %%%LICENSE_START(GPLv2+_DOC_FULL)
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.\" This is free documentation; you can redistribute it and/or
.\" modify it under the terms of the GNU General Public License as
.\" published by the Free Software Foundation; either version 2 of
.\" the License, or (at your option) any later version.
.\"
.\" The GNU General Public License's references to "object code"
.\" and "executables" are to be interpreted as the output of any
.\" document formatting or typesetting system, including
.\" intermediate and printed output.
.\"
.\" This manual is distributed in the hope that it will be useful,
.\" but WITHOUT ANY WARRANTY; without even the implied warranty of
.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
.\" GNU General Public License for more details.
.\"
.\" You should have received a copy of the GNU General Public
getent.1, _syscall.2, acct.2, adjtimex.2, bdflush.2, brk.2, cacheflush.2, getsid.2, getxattr.2, inotify_add_watch.2, inotify_init.2, inotify_rm_watch.2, ioperm.2, ipc.2, listxattr.2, mlock.2, modify_ldt.2, mremap.2, nanosleep.2, outb.2, ptrace.2, removexattr.2, sched_get_priority_max.2, sched_rr_get_interval.2, sched_setaffinity.2, sched_setparam.2, sched_setscheduler.2, sched_yield.2, setsid.2, setxattr.2, socketcall.2, unimplemented.2, aio_cancel.3, aio_error.3, aio_fsync.3, aio_read.3, aio_return.3, aio_suspend.3, aio_write.3, cfree.3, crypt.3, dlopen.3, errno.3, fenv.3, ftime.3, ftw.3, getgrent_r.3, getpass.3, getpwent_r.3, getutent.3, hsearch.3, lio_listio.3, login.3, longjmp.3, perror.3, printf.3, scandirat.3, setjmp.3, strfmon.3, strtoimax.3, termios.3, ttyname.3, ualarm.3, wcstoimax.3, wordexp.3, console_ioctl.4, dsp56k.4, fd.4, hd.4, intro.4, lp.4, mem.4, null.4, ram.4, rtc.4, sk98lin.4, tty.4, ttyS.4, vcs.4, charmap.5, filesystems.5, ftpusers.5, gai.conf.5, group.5, host.conf.5, hosts.5, intro.5, issue.5, locale.5, motd.5, networks.5, nologin.5, nscd.conf.5, nss.5, nsswitch.conf.5, passwd.5, proc.5, protocols.5, securetty.5, shells.5, termcap.5, ttytype.5, utmp.5, intro.6, armscii-8.7, ascii.7, bootparam.7, cp1251.7, cpuset.7, environ.7, glob.7, intro.7, iso_8859-1.7, iso_8859-10.7, iso_8859-11.7, iso_8859-13.7, iso_8859-14.7, iso_8859-15.7, iso_8859-16.7, iso_8859-2.7, iso_8859-3.7, iso_8859-4.7, iso_8859-5.7, iso_8859-6.7, iso_8859-7.7, iso_8859-8.7, iso_8859-9.7, koi8-r.7, koi8-u.7, posixoptions.7, standards.7, unicode.7, utf-8.7, intro.8, ldconfig.8, nscd.8: Global fix: Update info in source comments on where to get a copy of the GPL Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-03-10 09:28:43 +00:00
.\" License along with this manual; if not, see
.\" <http://www.gnu.org/licenses/>.
getent.1, _syscall.2, acct.2, adjtimex.2, bdflush.2, brk.2, cacheflush.2, getsid.2, getxattr.2, inotify_add_watch.2, inotify_init.2, inotify_rm_watch.2, ioperm.2, ipc.2, listxattr.2, mlock.2, modify_ldt.2, mremap.2, nanosleep.2, outb.2, perf_event_open.2, ptrace.2, removexattr.2, s390_runtime_instr.2, sched_get_priority_max.2, sched_rr_get_interval.2, sched_setaffinity.2, sched_setparam.2, sched_setscheduler.2, sched_yield.2, setsid.2, setxattr.2, socketcall.2, unimplemented.2, aio_cancel.3, aio_error.3, aio_fsync.3, aio_read.3, aio_return.3, aio_suspend.3, aio_write.3, cfree.3, crypt.3, dlopen.3, encrypt.3, errno.3, fenv.3, ftime.3, ftw.3, getgrent_r.3, getpass.3, getpwent_r.3, getutent.3, hsearch.3, lio_listio.3, lockf.3, login.3, longjmp.3, perror.3, printf.3, scandirat.3, setjmp.3, strfmon.3, strtoimax.3, termios.3, ttyname.3, ualarm.3, updwtmp.3, wcstoimax.3, wordexp.3, console_ioctl.4, dsp56k.4, fd.4, hd.4, intro.4, lp.4, mem.4, null.4, ram.4, rtc.4, sk98lin.4, tty.4, ttyS.4, vcs.4, filesystems.5, group.5, host.conf.5, hosts.5, intro.5, issue.5, motd.5, networks.5, nologin.5, nsswitch.conf.5, passwd.5, proc.5, protocols.5, securetty.5, shells.5, termcap.5, ttytype.5, utmp.5, intro.6, armscii-8.7, ascii.7, bootparam.7, cp1251.7, environ.7, glob.7, intro.7, iso_8859-1.7, iso_8859-10.7, iso_8859-11.7, iso_8859-13.7, iso_8859-14.7, iso_8859-15.7, iso_8859-16.7, iso_8859-2.7, iso_8859-3.7, iso_8859-4.7, iso_8859-5.7, iso_8859-6.7, iso_8859-7.7, iso_8859-8.7, iso_8859-9.7, koi8-r.7, koi8-u.7, posixoptions.7, standards.7, unicode.7, utf-8.7, intro.8: Global fix: Add LICENSE_START(GPLv2+_doc_full) Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
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.\" %%%LICENSE_END
.\"
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.\" Modified Sun Jul 25 10:45:30 1993 by Rik Faith (faith@cs.unc.edu)
.\" Modified Sun Jul 21 21:25:26 1996 by Andries Brouwer (aeb@cwi.nl)
.\" Modified Mon Oct 21 17:47:19 1996 by Eric S. Raymond (esr@thyrsus.com)
.\" Modified Wed Aug 27 20:28:58 1997 by Nicolás Lichtmaier (nick@debian.org)
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.\" Modified Mon Sep 21 00:00:26 1998 by Andries Brouwer (aeb@cwi.nl)
.\" Modified Wed Jan 24 06:37:24 2001 by Eric S. Raymond (esr@thyrsus.com)
.\" Modified Thu Dec 13 23:53:27 2001 by Martin Schulze <joey@infodrom.org>
.\"
2020-08-13 08:01:14 +00:00
.TH ENVIRON 7 2020-08-13 "Linux" "Linux Programmer's Manual"
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.SH NAME
environ \- user environment
.SH SYNOPSIS
.nf
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.BI "extern char **" environ ;
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.fi
.SH DESCRIPTION
The variable
.I environ
points to an array of pointers to strings called the "environment".
The last pointer in this array has the value NULL.
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This array of strings is made available to the process by the
.BR execve (2)
call when a new program is started.
When a child process is created via
.BR fork (2),
it inherits a
.I copy
of its parent's environment.
.PP
By convention, the strings in
.I environ
have the form "\fIname\fP\fB=\fP\fIvalue\fP".
The name is case-sensitive and may not contain
the character "\fB=\fP".
The value can be anything that can be represented as a string.
The name and the value may not contain an embedded null byte (\(aq\e0\(aq),
since this is assumed to terminate the string.
.PP
Common examples are:
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.TP
.B USER
The name of the logged-in user (used by some BSD-derived programs).
.TP
.B LOGNAME
The name of the logged-in user (used by some System-V derived programs).
.TP
.B HOME
A user's login directory, set by
.BR login (1)
from the password file
.BR passwd (5).
.TP
.B LANG
The name of a locale to use for locale categories when not overridden
by
.B LC_ALL
or more specific environment variables such as
.BR LC_COLLATE ,
.BR LC_CTYPE ,
.BR LC_MESSAGES ,
.BR LC_MONETARY ,
.BR LC_NUMERIC ,
and
.BR LC_TIME
(see
.BR locale (7)
for further details of the
.BR LC_*
environment variables).
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.TP
.B PATH
The sequence of directory prefixes that
.BR sh (1)
and many other
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programs apply in searching for a file known by an incomplete pathname.
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The prefixes are separated by \(aq\fB:\fP\(aq.
(Similarly one has
.B CDPATH
used by some shells to find the target
of a change directory command,
.B MANPATH
used by
.BR man (1)
to find manual pages, and so on)
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.TP
.B PWD
The current working directory.
Set by some shells.
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.TP
.B SHELL
environ.7: Document valid values of pathnames for SHELL, PAGER and EDITOR/VISUAL The environ(7) man page says: SHELL The pathname of the user's login shell. PAGER The user's preferred utility to display text files. EDITOR/VISUAL The user's preferred utility to edit text files. but doesn't say whether the pathnames must be absolute or they can be resolved using $PATH, or whether they can have options. Note that at least for SHELL, this is not specified by POSIX. This issue was raised in the Austin Group mailing-list, and the answer is that "what constitutes a valid value for a platform should be documented" [1]. Since OpenSSH assumes that $SHELL is an absolute pathname (when set), it is supposed that the documentation should be: SHELL The absolute pathname of the user's login shell. For PAGER, POSIX says: "Any string acceptable as a command_string operand to the sh -c command shall be valid." For EDITOR, it does not need to be an absolute pathname since POSIX gives the example: EDITOR=vi fc and since it is specified as "the name of a utility", It assumes that arguments (options) must not be provided. Page 3013 about "more", it is said: "If the last pathname component in EDITOR is either vi or ex, [...]", thus again, it is assumed to be a pathname. For VISUAL, POSIX says: "Determine a pathname of a utility to invoke when the visual command [...]", thus it is also a pathname. It is not clear whether the pathname must be absolute, but for consistency with EDITOR, it will be resolved using $PATH. [1] https://www.mail-archive.com/austin-group-l@opengroup.org/msg01399.html Reported-by: Vincent Lefevre <vincent@vinc17.net> Signed-off-by: Bastien Roucaries <rouca@debian.org> Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com> Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
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The absolute pathname of the user's login shell.
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.TP
.B TERM
The terminal type for which output is to be prepared.
.TP
.B PAGER
The user's preferred utility to display text files.
environ.7: Document valid values of pathnames for SHELL, PAGER and EDITOR/VISUAL The environ(7) man page says: SHELL The pathname of the user's login shell. PAGER The user's preferred utility to display text files. EDITOR/VISUAL The user's preferred utility to edit text files. but doesn't say whether the pathnames must be absolute or they can be resolved using $PATH, or whether they can have options. Note that at least for SHELL, this is not specified by POSIX. This issue was raised in the Austin Group mailing-list, and the answer is that "what constitutes a valid value for a platform should be documented" [1]. Since OpenSSH assumes that $SHELL is an absolute pathname (when set), it is supposed that the documentation should be: SHELL The absolute pathname of the user's login shell. For PAGER, POSIX says: "Any string acceptable as a command_string operand to the sh -c command shall be valid." For EDITOR, it does not need to be an absolute pathname since POSIX gives the example: EDITOR=vi fc and since it is specified as "the name of a utility", It assumes that arguments (options) must not be provided. Page 3013 about "more", it is said: "If the last pathname component in EDITOR is either vi or ex, [...]", thus again, it is assumed to be a pathname. For VISUAL, POSIX says: "Determine a pathname of a utility to invoke when the visual command [...]", thus it is also a pathname. It is not clear whether the pathname must be absolute, but for consistency with EDITOR, it will be resolved using $PATH. [1] https://www.mail-archive.com/austin-group-l@opengroup.org/msg01399.html Reported-by: Vincent Lefevre <vincent@vinc17.net> Signed-off-by: Bastien Roucaries <rouca@debian.org> Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com> Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
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Any string acceptable as a command_string operand to the
.I sh\ \-c
environ.7: Document valid values of pathnames for SHELL, PAGER and EDITOR/VISUAL The environ(7) man page says: SHELL The pathname of the user's login shell. PAGER The user's preferred utility to display text files. EDITOR/VISUAL The user's preferred utility to edit text files. but doesn't say whether the pathnames must be absolute or they can be resolved using $PATH, or whether they can have options. Note that at least for SHELL, this is not specified by POSIX. This issue was raised in the Austin Group mailing-list, and the answer is that "what constitutes a valid value for a platform should be documented" [1]. Since OpenSSH assumes that $SHELL is an absolute pathname (when set), it is supposed that the documentation should be: SHELL The absolute pathname of the user's login shell. For PAGER, POSIX says: "Any string acceptable as a command_string operand to the sh -c command shall be valid." For EDITOR, it does not need to be an absolute pathname since POSIX gives the example: EDITOR=vi fc and since it is specified as "the name of a utility", It assumes that arguments (options) must not be provided. Page 3013 about "more", it is said: "If the last pathname component in EDITOR is either vi or ex, [...]", thus again, it is assumed to be a pathname. For VISUAL, POSIX says: "Determine a pathname of a utility to invoke when the visual command [...]", thus it is also a pathname. It is not clear whether the pathname must be absolute, but for consistency with EDITOR, it will be resolved using $PATH. [1] https://www.mail-archive.com/austin-group-l@opengroup.org/msg01399.html Reported-by: Vincent Lefevre <vincent@vinc17.net> Signed-off-by: Bastien Roucaries <rouca@debian.org> Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com> Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
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command shall be valid.
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.TP
.BR EDITOR / VISUAL
The user's preferred utility to edit text files.
environ.7: Document valid values of pathnames for SHELL, PAGER and EDITOR/VISUAL The environ(7) man page says: SHELL The pathname of the user's login shell. PAGER The user's preferred utility to display text files. EDITOR/VISUAL The user's preferred utility to edit text files. but doesn't say whether the pathnames must be absolute or they can be resolved using $PATH, or whether they can have options. Note that at least for SHELL, this is not specified by POSIX. This issue was raised in the Austin Group mailing-list, and the answer is that "what constitutes a valid value for a platform should be documented" [1]. Since OpenSSH assumes that $SHELL is an absolute pathname (when set), it is supposed that the documentation should be: SHELL The absolute pathname of the user's login shell. For PAGER, POSIX says: "Any string acceptable as a command_string operand to the sh -c command shall be valid." For EDITOR, it does not need to be an absolute pathname since POSIX gives the example: EDITOR=vi fc and since it is specified as "the name of a utility", It assumes that arguments (options) must not be provided. Page 3013 about "more", it is said: "If the last pathname component in EDITOR is either vi or ex, [...]", thus again, it is assumed to be a pathname. For VISUAL, POSIX says: "Determine a pathname of a utility to invoke when the visual command [...]", thus it is also a pathname. It is not clear whether the pathname must be absolute, but for consistency with EDITOR, it will be resolved using $PATH. [1] https://www.mail-archive.com/austin-group-l@opengroup.org/msg01399.html Reported-by: Vincent Lefevre <vincent@vinc17.net> Signed-off-by: Bastien Roucaries <rouca@debian.org> Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com> Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
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Any string acceptable as a command_string operand to the
.I sh\ \-c
environ.7: Document valid values of pathnames for SHELL, PAGER and EDITOR/VISUAL The environ(7) man page says: SHELL The pathname of the user's login shell. PAGER The user's preferred utility to display text files. EDITOR/VISUAL The user's preferred utility to edit text files. but doesn't say whether the pathnames must be absolute or they can be resolved using $PATH, or whether they can have options. Note that at least for SHELL, this is not specified by POSIX. This issue was raised in the Austin Group mailing-list, and the answer is that "what constitutes a valid value for a platform should be documented" [1]. Since OpenSSH assumes that $SHELL is an absolute pathname (when set), it is supposed that the documentation should be: SHELL The absolute pathname of the user's login shell. For PAGER, POSIX says: "Any string acceptable as a command_string operand to the sh -c command shall be valid." For EDITOR, it does not need to be an absolute pathname since POSIX gives the example: EDITOR=vi fc and since it is specified as "the name of a utility", It assumes that arguments (options) must not be provided. Page 3013 about "more", it is said: "If the last pathname component in EDITOR is either vi or ex, [...]", thus again, it is assumed to be a pathname. For VISUAL, POSIX says: "Determine a pathname of a utility to invoke when the visual command [...]", thus it is also a pathname. It is not clear whether the pathname must be absolute, but for consistency with EDITOR, it will be resolved using $PATH. [1] https://www.mail-archive.com/austin-group-l@opengroup.org/msg01399.html Reported-by: Vincent Lefevre <vincent@vinc17.net> Signed-off-by: Bastien Roucaries <rouca@debian.org> Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com> Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
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command shall be valid.
.\" .TP
.\" .B BROWSER
.\" The user's preferred utility to browse URLs. Sequence of colon-separated
.\" browser commands. See http://www.catb.org/\(tiesr/BROWSER/ .
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.PP
Names may be placed in the shell's environment by the
.I export
command in
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.BR sh (1),
or by the
.I setenv
command if you use
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.BR csh (1).
.PP
The initial environment of the shell is populated in various ways,
such as definitions from
.IR /etc/environment
that are processed by
.BR pam_env (8)
for all users at login time (on systems that employ
.BR pam (8)).
In addition, various shell initialization scripts, such as the system-wide
.IR /etc/profile
script and per-user initializations script may include commands
that add variables to the shell's environment;
see the manual page of your preferred shell for details.
.PP
Bourne-style shells support the syntax
.PP
NAME=value command
.PP
to create an environment variable definition only in the scope
of the process that executes
.IR command .
Multiple variable definitions, separated by white space, may precede
.IR command .
.PP
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Arguments may also be placed in the
environment at the point of an
.BR exec (3).
A C program can manipulate its environment using the functions
.BR getenv (3),
.BR putenv (3),
.BR setenv (3),
and
.BR unsetenv (3).
.PP
Note that the behavior of many programs and library routines is
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influenced by the presence or value of certain environment variables.
Examples include the following:
.IP * 3
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The variables
.BR LANG ", " LANGUAGE ", " NLSPATH ", " LOCPATH ,
.BR LC_ALL ", " LC_MESSAGES ,
and so on influence locale handling; see
.BR catopen (3),
.BR gettext (3),
and
.BR locale (7).
.IP *
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.B TMPDIR
influences the path prefix of names created by
.BR tempnam (3)
and other routines, and the temporary directory used by
.BR sort (1)
and other programs.
.IP *
.BR LD_LIBRARY_PATH ", " LD_PRELOAD ,
and other
.BR LD_*
variables influence the behavior of the dynamic loader/linker.
See also
.BR ld.so (8).
.IP *
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.B POSIXLY_CORRECT
makes certain programs and library routines follow
the prescriptions of POSIX.
.IP *
The behavior of
.BR malloc (3)
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is influenced by
.B MALLOC_*
variables.
.IP *
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The variable
.B HOSTALIASES
gives the name of a file containing aliases
to be used with
.BR gethostbyname (3).
.IP *
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.BR TZ " and " TZDIR
give timezone information used by
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.BR tzset (3)
and through that by functions like
.BR ctime (3),
.BR localtime (3),
.BR mktime (3),
.BR strftime (3).
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See also
.BR tzselect (8).
.IP *
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.B TERMCAP
gives information on how to address a given terminal
(or gives the name of a file containing such information).
.IP *
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.BR COLUMNS " and " LINES
tell applications about the window size, possibly overriding the actual size.
.IP *
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.BR PRINTER " or " LPDEST
may specify the desired printer to use.
See
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.BR lpr (1).
.SH NOTES
Historically and by standard,
.I environ
must be declared in the user program.
However, as a (nonstandard) programmer convenience,
.I environ
is declared in the header file
.I <unistd.h>
if the
.B _GNU_SOURCE
feature test macro is defined (see
.BR feature_test_macros (7)).
.PP
The
.BR prctl (2)
.B PR_SET_MM_ENV_START
and
.B PR_SET_MM_ENV_END
operations can be used to control the location of the process's environment.
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.SH BUGS
Clearly there is a security risk here.
Many a system command has been
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tricked into mischief by a user who specified unusual values for
.BR IFS " or " LD_LIBRARY_PATH .
.PP
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There is also the risk of name space pollution.
Programs like
.I make
and
.I autoconf
allow overriding of default utility names from the
environment with similarly named variables in all caps.
Thus one uses
.B CC
to select the desired C compiler (and similarly
.BR MAKE ,
.BR AR ,
.BR AS ,
.BR FC ,
.BR LD ,
.BR LEX ,
.BR RM ,
.BR YACC ,
etc.).
However, in some traditional uses such an environment variable
gives options for the program instead of a pathname.
Thus, one has
.BR MORE ,
.BR LESS ,
and
.BR GZIP .
Such usage is considered mistaken, and to be avoided in new
programs.
The authors of
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.I gzip
should consider renaming their option to
.BR GZIP_OPT .
getent.1, intro.1, time.1, _exit.2, _syscall.2, accept.2, access.2, acct.2, adjtimex.2, alarm.2, alloc_hugepages.2, arch_prctl.2, bdflush.2, bind.2, brk.2, cacheflush.2, capget.2, chdir.2, chmod.2, chown.2, chroot.2, clock_getres.2, clock_nanosleep.2, clone.2, close.2, connect.2, create_module.2, delete_module.2, dup.2, epoll_create.2, epoll_ctl.2, epoll_wait.2, eventfd.2, execve.2, exit_group.2, faccessat.2, fchmodat.2, fchownat.2, fcntl.2, flock.2, fork.2, fstatat.2, fsync.2, futex.2, futimesat.2, get_kernel_syms.2, get_robust_list.2, get_thread_area.2, getcpu.2, getdents.2, getdomainname.2, getgid.2, getgroups.2, gethostname.2, getitimer.2, getpagesize.2, getpeername.2, getpid.2, getpriority.2, getresuid.2, getrlimit.2, getrusage.2, getsid.2, getsockname.2, getsockopt.2, gettid.2, gettimeofday.2, getuid.2, getunwind.2, getxattr.2, idle.2, init_module.2, inotify_add_watch.2, inotify_init.2, inotify_rm_watch.2, intro.2, io_cancel.2, io_destroy.2, io_getevents.2, io_setup.2, io_submit.2, ioctl.2, ioctl_list.2, ioperm.2, iopl.2, ioprio_set.2, ipc.2, kcmp.2, kill.2, killpg.2, link.2, linkat.2, listen.2, listxattr.2, llseek.2, lookup_dcookie.2, lseek.2, madvise.2, migrate_pages.2, mincore.2, mkdir.2, mkdirat.2, mknod.2, mknodat.2, mlock.2, mmap.2, mmap2.2, modify_ldt.2, mount.2, move_pages.2, mprotect.2, mq_getsetattr.2, mremap.2, msgctl.2, msgget.2, msgop.2, msync.2, nanosleep.2, nfsservctl.2, nice.2, open.2, openat.2, outb.2, pause.2, pciconfig_read.2, perf_event_open.2, perfmonctl.2, personality.2, pipe.2, pivot_root.2, poll.2, posix_fadvise.2, prctl.2, pread.2, process_vm_readv.2, ptrace.2, query_module.2, quotactl.2, read.2, readahead.2, readdir.2, readlink.2, readlinkat.2, readv.2, reboot.2, recv.2, remap_file_pages.2, removexattr.2, rename.2, renameat.2, rmdir.2, rt_sigqueueinfo.2, sched_get_priority_max.2, sched_rr_get_interval.2, sched_setaffinity.2, sched_setparam.2, sched_setscheduler.2, sched_yield.2, select.2, semctl.2, semget.2, semop.2, send.2, sendfile.2, set_thread_area.2, set_tid_address.2, seteuid.2, setfsgid.2, setfsuid.2, setgid.2, setpgid.2, setresuid.2, setreuid.2, setsid.2, setuid.2, setup.2, setxattr.2, shmctl.2, shmget.2, shmop.2, shutdown.2, sigaction.2, sigaltstack.2, signal.2, signalfd.2, sigpending.2, sigprocmask.2, sigreturn.2, sigsuspend.2, sigwaitinfo.2, socket.2, socketcall.2, socketpair.2, splice.2, stat.2, statfs.2, stime.2, swapon.2, symlink.2, symlinkat.2, sync.2, sync_file_range.2, sysctl.2, sysfs.2, sysinfo.2, syslog.2, tee.2, time.2, timerfd_create.2, times.2, tkill.2, truncate.2, umask.2, umount.2, uname.2, unimplemented.2, unlink.2, unlinkat.2, uselib.2, ustat.2, utime.2, utimensat.2, vfork.2, vhangup.2, vm86.2, vmsplice.2, wait.2, wait4.2, write.2, CPU_SET.3, INFINITY.3, MB_CUR_MAX.3, MB_LEN_MAX.3, __setfpucw.3, a64l.3, abort.3, abs.3, acos.3, acosh.3, addseverity.3, adjtime.3, aio_cancel.3, aio_error.3, aio_fsync.3, aio_read.3, aio_return.3, aio_suspend.3, aio_write.3, alloca.3, argz_add.3, asin.3, asinh.3, asprintf.3, assert.3, assert_perror.3, atan.3, atan2.3, atanh.3, atexit.3, atof.3, atoi.3, backtrace.3, basename.3, bcmp.3, bcopy.3, bindresvport.3, bsd_signal.3, bsearch.3, bstring.3, btowc.3, btree.3, byteorder.3, bzero.3, cabs.3, cacos.3, cacosh.3, canonicalize_file_name.3, carg.3, casin.3, casinh.3, catan.3, catanh.3, catgets.3, catopen.3, cbrt.3, ccos.3, ccosh.3, ceil.3, cerf.3, cexp.3, cexp2.3, cfree.3, cimag.3, clearenv.3, clock.3, clock_getcpuclockid.3, clog.3, clog10.3, clog2.3, closedir.3, cmsg.3, confstr.3, conj.3, copysign.3, cos.3, cosh.3, cpow.3, cproj.3, creal.3, crypt.3, csin.3, csinh.3, csqrt.3, ctan.3, ctanh.3, ctermid.3, ctime.3, daemon.3, dbopen.3, des_crypt.3, difftime.3, dirfd.3, div.3, dl_iterate_phdr.3, dlopen.3, dprintf.3, drand48.3, drand48_r.3, dysize.3, ecvt.3, ecvt_r.3, encrypt.3, end.3, endian.3, envz_add.3, erf.3, erfc.3, err.3, errno.3, error.3, ether_aton.3, euidaccess.3, exec.3, exit.3, exp.3, exp10.3, exp2.3, expm1.3, fabs.3, fclose.3, fcloseall.3, fdim.3, fenv.3, ferror.3, fexecve.3, fflush.3, ffs.3, fgetgrent.3, fgetpwent.3, fgetwc.3, fgetws.3, finite.3, flockfile.3, floor.3, fma.3, fmax.3, fmemopen.3, fmin.3, fmod.3, fmtmsg.3, fnmatch.3, fopen.3, fpathconf.3, fpclassify.3, fpurge.3, fputwc.3, fputws.3, fread.3, frexp.3, fseek.3, fseeko.3, ftime.3, ftok.3, fts.3, ftw.3, futimes.3, fwide.3, gamma.3, gcvt.3, getaddrinfo.3, getaddrinfo_a.3, getauxval.3, getcontext.3, getcwd.3, getdate.3, getdirentries.3, getdtablesize.3, getenv.3, getfsent.3, getgrent.3, getgrent_r.3, getgrnam.3, getgrouplist.3, gethostbyname.3, gethostid.3, getipnodebyname.3, getline.3, getloadavg.3, getlogin.3, getmntent.3, getnameinfo.3, getnetent.3, getnetent_r.3, getopt.3, getpass.3, getprotoent.3, getprotoent_r.3, getpt.3, getpw.3, getpwent.3, getpwent_r.3, getpwnam.3, getrpcent.3, getrpcent_r.3, getrpcport.3, gets.3, getservent.3, getservent_r.3, getspnam.3, getttyent.3, getumask.3, getusershell.3, getutent.3, getw.3, getwchar.3, glob.3, grantpt.3, gsignal.3, hash.3, hsearch.3, hypot.3, iconv.3, iconv_close.3, iconv_open.3, ilogb.3, index.3, inet.3, inet_ntop.3, inet_pton.3, infnan.3, initgroups.3, insque.3, intro.3, isalpha.3, isatty.3, isgreater.3, iswalnum.3, iswalpha.3, iswblank.3, iswcntrl.3, iswctype.3, iswdigit.3, iswgraph.3, iswlower.3, iswprint.3, iswpunct.3, iswspace.3, iswupper.3, iswxdigit.3, j0.3, key_setsecret.3, ldexp.3, lgamma.3, lio_listio.3, localeconv.3, lockf.3, log.3, log10.3, log1p.3, log2.3, logb.3, login.3, longjmp.3, lrint.3, lround.3, lsearch.3, lseek64.3, makecontext.3, makedev.3, malloc.3, malloc_hook.3, mblen.3, mbrlen.3, mbrtowc.3, mbsinit.3, mbsnrtowcs.3, mbsrtowcs.3, mbstowcs.3, mbtowc.3, memccpy.3, memchr.3, memcmp.3, memcpy.3, memfrob.3, memmem.3, memmove.3, mempcpy.3, memset.3, mkdtemp.3, mkfifo.3, mkfifoat.3, mkstemp.3, mktemp.3, modf.3, mpool.3, mq_close.3, mq_getattr.3, mq_notify.3, mq_open.3, mq_receive.3, mq_send.3, mq_unlink.3, mtrace.3, nan.3, netlink.3, nextafter.3, nl_langinfo.3, offsetof.3, on_exit.3, opendir.3, openpty.3, perror.3, popen.3, posix_fallocate.3, posix_memalign.3, posix_openpt.3, pow.3, pow10.3, printf.3, profil.3, program_invocation_name.3, psignal.3, pthread_kill_other_threads_np.3, ptsname.3, putenv.3, putgrent.3, putpwent.3, puts.3, putwchar.3, qecvt.3, qsort.3, queue.3, raise.3, rand.3, random.3, random_r.3, rcmd.3, re_comp.3, readdir.3, realpath.3, recno.3, regex.3, remainder.3, remove.3, remquo.3, resolver.3, rewinddir.3, rexec.3, rint.3, round.3, rpc.3, rpmatch.3, rtime.3, rtnetlink.3, scalb.3, scalbln.3, scandir.3, scandirat.3, scanf.3, seekdir.3, sem_close.3, sem_destroy.3, sem_getvalue.3, sem_init.3, sem_open.3, sem_post.3, sem_unlink.3, sem_wait.3, setaliasent.3, setbuf.3, setenv.3, setjmp.3, setlocale.3, setlogmask.3, setnetgrent.3, shm_open.3, siginterrupt.3, signbit.3, significand.3, sigpause.3, sigqueue.3, sigset.3, sigsetops.3, sigvec.3, sin.3, sincos.3, sinh.3, sleep.3, sockatmark.3, sqrt.3, statvfs.3, stdarg.3, stdin.3, stdio.3, stdio_ext.3, stpcpy.3, stpncpy.3, strcasecmp.3, strcat.3, strchr.3, strcmp.3, strcoll.3, strcpy.3, strdup.3, strerror.3, strfmon.3, strfry.3, strftime.3, string.3, strlen.3, strnlen.3, strpbrk.3, strptime.3, strsep.3, strsignal.3, strspn.3, strstr.3, strtod.3, strtoimax.3, strtok.3, strtol.3, strtoul.3, strverscmp.3, strxfrm.3, swab.3, sysconf.3, syslog.3, system.3, sysv_signal.3, tan.3, tanh.3, tcgetpgrp.3, tcgetsid.3, telldir.3, tempnam.3, termios.3, tgamma.3, timegm.3, timeradd.3, tmpfile.3, tmpnam.3, toascii.3, toupper.3, towctrans.3, towlower.3, towupper.3, trunc.3, tsearch.3, ttyname.3, ttyslot.3, tzset.3, ualarm.3, ulimit.3, ungetwc.3, unlocked_stdio.3, unlockpt.3, updwtmp.3, usleep.3, wcpcpy.3, wcpncpy.3, wcrtomb.3, wcscasecmp.3, wcscat.3, wcschr.3, wcscmp.3, wcscpy.3, wcscspn.3, wcsdup.3, wcslen.3, wcsncasecmp.3, wcsncat.3, wcsncmp.3, wcsncpy.3, wcsnlen.3, wcsnrtombs.3, wcspbrk.3, wcsrchr.3, wcsrtombs.3, wcsspn.3, wcsstr.3, wcstoimax.3, wcstok.3, wcstombs.3, wcswidth.3, wctob.3, wctomb.3, wctrans.3, wctype.3, wcwidth.3, wmemchr.3, wmemcmp.3, wmemcpy.3, wmemmove.3, wmemset.3, wordexp.3, wprintf.3, xcrypt.3, xdr.3, y0.3, cciss.4, console.4, console_codes.4, console_ioctl.4, dsp56k.4, fd.4, full.4, hd.4, hpsa.4, initrd.4, intro.4, lp.4, mem.4, mouse.4, null.4, pts.4, ram.4, random.4, rtc.4, sk98lin.4, st.4, tty.4, ttyS.4, tty_ioctl.4, vcs.4, wavelan.4, acct.5, charmap.5, dir_colors.5, filesystems.5, ftpusers.5, group.5, host.conf.5, hosts.5, hosts.equiv.5, intro.5, issue.5, locale.5, motd.5, networks.5, nologin.5, nscd.conf.5, passwd.5, proc.5, protocols.5, resolv.conf.5, rpc.5, securetty.5, services.5, shells.5, termcap.5, ttytype.5, utmp.5, armscii-8.7, arp.7, ascii.7, bootparam.7, capabilities.7, charsets.7, complex.7, cp1251.7, credentials.7, ddp.7, environ.7, epoll.7, fifo.7, futex.7, glob.7, hier.7, icmp.7, inotify.7, intro.7, ip.7, ipv6.7, iso_8859-1.7, iso_8859-10.7, iso_8859-11.7, iso_8859-13.7, iso_8859-14.7, iso_8859-15.7, iso_8859-16.7, iso_8859-2.7, iso_8859-3.7, iso_8859-4.7, iso_8859-5.7, iso_8859-6.7, iso_8859-7.7, iso_8859-8.7, iso_8859-9.7, koi8-r.7, koi8-u.7, locale.7, mailaddr.7, man.7, mq_overview.7, netdevice.7, netlink.7, numa.7, packet.7, path_resolution.7, pipe.7, posixoptions.7, pthreads.7, pty.7, raw.7, regex.7, rtld-audit.7, rtnetlink.7, sem_overview.7, shm_overview.7, sigevent.7, signal.7, socket.7, standards.7, suffixes.7, svipc.7, tcp.7, termio.7, time.7, udp.7, udplite.7, unicode.7, unix.7, uri.7, utf-8.7, x25.7, nscd.8, sync.8, tzselect.8, zdump.8, zic.8: Global fix: remove unneeded double quotes in .SH headings Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-02-24 18:01:36 +00:00
.SH SEE ALSO
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.BR bash (1),
.BR csh (1),
.BR env (1),
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.BR login (1),
.BR printenv (1),
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.BR sh (1),
.BR tcsh (1),
.BR execve (2),
.BR clearenv (3),
.BR exec (3),
.BR getenv (3),
.BR putenv (3),
.BR setenv (3),
.BR unsetenv (3),
.BR locale (7),
.BR ld.so (8),
.BR pam_env (8)