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SUDO(8)			FreeBSD	System Manager's Manual		       SUDO(8)

NAME
     sudo, sudoedit -- execute a command as another user

SYNOPSIS
     sudo -h | -K | -k | -V
     sudo -v [-ABknS] [-g group] [-h host] [-p prompt] [-u user]
     sudo -l [-ABknS] [-g group] [-h host] [-p prompt] [-U user] [-u user]
	  [command]
     sudo [-ABbEHnPS] [-C num] [-c class] [-g group] [-h host] [-p prompt]
	  [-T timeout] [-u user] [VAR=value] [-i | -s] [command]
     sudoedit [-ABknS] [-C num]	[-c class] [-g group] [-h host]	[-p prompt]
	  [-T timeout] [-u user] file ...

DESCRIPTION
     sudo allows a permitted user to execute a command as the superuser	or an-
     other user, as specified by the security policy.  The invoking user's
     real (not effective) user-ID is used to determine the user	name with
     which to query the	security policy.

     sudo supports a plugin architecture for security policies and input/out-
     put logging.  Third parties can develop and distribute their own policy
     and I/O logging plugins to	work seamlessly	with the sudo front end.  The
     default security policy is	sudoers, which is configured via the file
     /usr/local/etc/sudoers, or	via LDAP.  See the Plugins section for more
     information.

     The security policy determines what privileges, if	any, a user has	to run
     sudo.  The	policy may require that	users authenticate themselves with a
     password or another authentication	mechanism.  If authentication is re-
     quired, sudo will exit if the user's password is not entered within a
     configurable time limit.  This limit is policy-specific; the default
     password prompt timeout for the sudoers security policy is	5 minutes.

     Security policies may support credential caching to allow the user	to run
     sudo again	for a period of	time without requiring authentication.	By de-
     fault, the	sudoers	policy caches credentials on a per-terminal basis for
     5 minutes.	 See the timestamp_type	and timestamp_timeout options in
     sudoers(5)	for more information.  By running sudo with the	-v option, a
     user can update the cached	credentials without running a command.

     When invoked as sudoedit, the -e option (described	below),	is implied.

     Security policies may log successful and failed attempts to use sudo.  If
     an	I/O plugin is configured, the running command's	input and output may
     be	logged as well.

     The options are as	follows:

     -A, --askpass
		 Normally, if sudo requires a password,	it will	read it	from
		 the user's terminal.  If the -A (askpass) option is speci-
		 fied, a (possibly graphical) helper program is	executed to
		 read the user's password and output the password to the stan-
		 dard output.  If the SUDO_ASKPASS environment variable	is
		 set, it specifies the path to the helper program.  Otherwise,
		 if sudo.conf(5) contains a line specifying the	askpass	pro-
		 gram, that value will be used.	 For example:

		     # Path to askpass helper program
		     Path askpass /usr/X11R6/bin/ssh-askpass

		 If no askpass program is available, sudo will exit with an
		 error.

     -B, --bell	 Ring the bell as part of the password promp when a terminal
		 is present.  This option has no effect	if an askpass program
		 is used.

     -b, --background
		 Run the given command in the background.  Note	that it	is not
		 possible to use shell job control to manipulate background
		 processes started by sudo.  Most interactive commands will
		 fail to work properly in background mode.

     -C	num, --close-from=num
		 Close all file	descriptors greater than or equal to num be-
		 fore executing	a command.  Values less	than three are not
		 permitted.  By	default, sudo will close all open file de-
		 scriptors other than standard input, standard output and
		 standard error	when executing a command.  The security	policy
		 may restrict the user's ability to use	this option.  The
		 sudoers policy	only permits use of the	-C option when the ad-
		 ministrator has enabled the closefrom_override	option.

     -c	class, --login-class=class
		 Run the command with resource limits and scheduling priority
		 of the	specified login	class.	The class argument can be ei-
		 ther a	class name as defined in /etc/login.conf, or a single
		 `-' character.	 If class is -,	the default login class	of the
		 target	user will be used.  Otherwise, the command must	be run
		 as the	superuser (user-ID 0), or sudo must be run from	a
		 shell that is already running as the superuser.  If the com-
		 mand is being run as a	login shell, additional
		 /etc/login.conf settings, such	as the umask and environment
		 variables, will be applied, if	present.  This option is only
		 available on systems with BSD login classes.

     -E, --preserve-env
		 Indicates to the security policy that the user	wishes to pre-
		 serve their existing environment variables.  The security
		 policy	may return an error if the user	does not have permis-
		 sion to preserve the environment.

     --preserve-env=list
		 Indicates to the security policy that the user	wishes to add
		 the comma-separated list of environment variables to those
		 preserved from	the user's environment.	 The security policy
		 may return an error if	the user does not have permission to
		 preserve the environment.  This option	may be specified mul-
		 tiple times.

     -e, --edit	 Edit one or more files	instead	of running a command.  In lieu
		 of a path name, the string "sudoedit" is used when consulting
		 the security policy.  If the user is authorized by the	pol-
		 icy, the following steps are taken:

		 1.   Temporary	copies are made	of the files to	be edited with
		      the owner	set to the invoking user.

		 2.   The editor specified by the policy is run	to edit	the
		      temporary	files.	The sudoers policy uses	the
		      SUDO_EDITOR, VISUAL and EDITOR environment variables (in
		      that order).  If none of SUDO_EDITOR, VISUAL or EDITOR
		      are set, the first program listed	in the editor
		      sudoers(5) option	is used.

		 3.   If they have been	modified, the temporary	files are
		      copied back to their original location and the temporary
		      versions are removed.

		 To help prevent the editing of	unauthorized files, the	fol-
		 lowing	restrictions are enforced unless explicitly allowed by
		 the security policy:

		 +o  Symbolic links may not be edited (version 1.8.15 and
		    higher).

		 +o  Symbolic links along the path to be	edited are not fol-
		    lowed when the parent directory is writable	by the invok-
		    ing	user unless that user is root (version 1.8.16 and
		    higher).

		 +o  Files located in a directory that is writable by the in-
		    voking user	may not	be edited unless that user is root
		    (version 1.8.16 and	higher).

		 Users are never allowed to edit device	special	files.

		 If the	specified file does not	exist, it will be created.
		 Note that unlike most commands	run by sudo, the editor	is run
		 with the invoking user's environment unmodified.  If, for
		 some reason, sudo is unable to	update a file with its edited
		 version, the user will	receive	a warning and the edited copy
		 will remain in	a temporary file.

     -g	group, --group=group
		 Run the command with the primary group	set to group instead
		 of the	primary	group specified	by the target user's password
		 database entry.  The group may	be either a group name or a
		 numeric group-ID (GID)	prefixed with the `#' character	(e.g.,
		 #0 for	GID 0).	 When running a	command	as a GID, many shells
		 require that the `#' be escaped with a	backslash (`\').  If
		 no -u option is specified, the	command	will be	run as the in-
		 voking	user.  In either case, the primary group will be set
		 to group.  The	sudoers	policy permits any of the target
		 user's	groups to be specified via the -g option as long as
		 the -P	option is not in use.

     -H, --set-home
		 Request that the security policy set the HOME environment
		 variable to the home directory	specified by the target	user's
		 password database entry.  Depending on	the policy, this may
		 be the	default	behavior.

     -h, --help	 Display a short help message to the standard output and exit.

     -h	host, --host=host
		 Run the command on the	specified host if the security policy
		 plugin	supports remote	commands.  Note	that the sudoers
		 plugin	does not currently support running remote commands.
		 This may also be used in conjunction with the -l option to
		 list a	user's privileges for the remote host.

     -i, --login
		 Run the shell specified by the	target user's password data-
		 base entry as a login shell.  This means that login-specific
		 resource files	such as	.profile, .bash_profile	or .login will
		 be read by the	shell.	If a command is	specified, it is
		 passed	to the shell for execution via the shell's -c option.
		 If no command is specified, an	interactive shell is executed.
		 sudo attempts to change to that user's	home directory before
		 running the shell.  The command is run	with an	environment
		 similar to the	one a user would receive at log	in.  Note that
		 most shells behave differently	when a command is specified as
		 compared to an	interactive session; consult the shell's man-
		 ual for details.  The Command environment section in the
		 sudoers(5) manual documents how the -i	option affects the en-
		 vironment in which a command is run when the sudoers policy
		 is in use.

     -K, --remove-timestamp
		 Similar to the	-k option, except that it removes the user's
		 cached	credentials entirely and may not be used in conjunc-
		 tion with a command or	other option.  This option does	not
		 require a password.  Not all security policies	support	cre-
		 dential caching.

     -k, --reset-timestamp
		 When used without a command, invalidates the user's cached
		 credentials.  In other	words, the next	time sudo is run a
		 password will be required.  This option does not require a
		 password and was added	to allow a user	to revoke sudo permis-
		 sions from a .logout file.

		 When used in conjunction with a command or an option that may
		 require a password, this option will cause sudo to ignore the
		 user's	cached credentials.  As	a result, sudo will prompt for
		 a password (if	one is required	by the security	policy)	and
		 will not update the user's cached credentials.

		 Not all security policies support credential caching.

     -l, --list	 If no command is specified, list the allowed (and forbidden)
		 commands for the invoking user	(or the	user specified by the
		 -U option) on the current host.  A longer list	format is used
		 if this option	is specified multiple times and	the security
		 policy	supports a verbose output format.

		 If a command is specified and is permitted by the security
		 policy, the fully-qualified path to the command is displayed
		 along with any	command	line arguments.	 If a command is spec-
		 ified but not allowed by the policy, sudo will	exit with a
		 status	value of 1.

     -n, --non-interactive
		 Avoid prompting the user for input of any kind.  If a pass-
		 word is required for the command to run, sudo will display an
		 error message and exit.

     -P, --preserve-groups
		 Preserve the invoking user's group vector unaltered.  By de-
		 fault,	the sudoers policy will	initialize the group vector to
		 the list of groups the	target user is a member	of.  The real
		 and effective group-IDs, however, are still set to match the
		 target	user.

     -p	prompt,	--prompt=prompt
		 Use a custom password prompt with optional escape sequences.
		 The following percent (`%') escape sequences are supported by
		 the sudoers policy:

		 %H  expanded to the host name including the domain name (on
		     if	the machine's host name	is fully qualified or the fqdn
		     option is set in sudoers(5))

		 %h  expanded to the local host	name without the domain	name

		 %p  expanded to the name of the user whose password is	being
		     requested (respects the rootpw, targetpw, and runaspw
		     flags in sudoers(5))

		 %U  expanded to the login name	of the user the	command	will
		     be	run as (defaults to root unless	the -u option is also
		     specified)

		 %u  expanded to the invoking user's login name

		 %%  two consecutive `%' characters are	collapsed into a sin-
		     gle `%' character

		 The custom prompt will	override the default prompt specified
		 by either the security	policy or the SUDO_PROMPT environment
		 variable.  On systems that use	PAM, the custom	prompt will
		 also override the prompt specified by a PAM module unless the
		 passprompt_override flag is disabled in sudoers.

     -S, --stdin
		 Write the prompt to the standard error	and read the password
		 from the standard input instead of using the terminal device.

     -s, --shell
		 Run the shell specified by the	SHELL environment variable if
		 it is set or the shell	specified by the invoking user's pass-
		 word database entry.  If a command is specified, it is	passed
		 to the	shell for execution via	the shell's -c option.	If no
		 command is specified, an interactive shell is executed.  Note
		 that most shells behave differently when a command is speci-
		 fied as compared to an	interactive session; consult the
		 shell's manual	for details.

     -U	user, --other-user=user
		 Used in conjunction with the -l option	to list	the privileges
		 for user instead of for the invoking user.  The security pol-
		 icy may restrict listing other	users' privileges.  The
		 sudoers policy	only allows root or a user with	the ALL	privi-
		 lege on the current host to use this option.

     -T	timeout, --command-timeout=timeout
		 Used to set a timeout for the command.	 If the	timeout	ex-
		 pires before the command has exited, the command will be ter-
		 minated.  The security	policy may restrict the	ability	to set
		 command timeouts.  The	sudoers	policy requires	that user-
		 specified timeouts be explicitly enabled.

     -u	user, --user=user
		 Run the command as a user other than the default target user
		 (usually root).  The user may be either a user	name or	a nu-
		 meric user-ID (UID) prefixed with the `#' character (e.g., #0
		 for UID 0).  When running commands as a UID, many shells re-
		 quire that the	`#' be escaped with a backslash	(`\').	Some
		 security policies may restrict	UIDs to	those listed in	the
		 password database.  The sudoers policy	allows UIDs that are
		 not in	the password database as long as the targetpw option
		 is not	set.  Other security policies may not support this.

     -V, --version
		 Print the sudo	version	string as well as the version string
		 of the	security policy	plugin and any I/O plugins.  If	the
		 invoking user is already root the -V option will display the
		 arguments passed to configure when sudo was built and plugins
		 may display more verbose information such as default options.

     -v, --validate
		 Update	the user's cached credentials, authenticating the user
		 if necessary.	For the	sudoers	plugin,	this extends the sudo
		 timeout for another 5 minutes by default, but does not	run a
		 command.  Not all security policies support cached creden-
		 tials.

     --		 The --	option indicates that sudo should stop processing com-
		 mand line arguments.

     Options that take a value may only	be specified once unless otherwise in-
     dicated in	the description.  This is to help guard	against	problems
     caused by poorly written scripts that invoke sudo with user-controlled
     input.

     Environment variables to be set for the command may also be passed	on the
     command line in the form of VAR=value, e.g.,
     LD_LIBRARY_PATH=/usr/local/pkg/lib.  Variables passed on the command line
     are subject to restrictions imposed by the	security policy	plugin.	 The
     sudoers policy subjects variables passed on the command line to the same
     restrictions as normal environment	variables with one important excep-
     tion.  If the setenv option is set	in sudoers, the	command	to be run has
     the SETENV	tag set	or the command matched is ALL, the user	may set	vari-
     ables that	would otherwise	be forbidden.  See sudoers(5) for more infor-
     mation.

COMMAND	EXECUTION
     When sudo executes	a command, the security	policy specifies the execution
     environment for the command.  Typically, the real and effective user and
     group and IDs are set to match those of the target	user, as specified in
     the password database, and	the group vector is initialized	based on the
     group database (unless the	-P option was specified).

     The following parameters may be specified by security policy:

     +o	real and effective user-ID

     +o	real and effective group-ID

     +o	supplementary group-IDs

     +o	the environment	list

     +o	current	working	directory

     +o	file creation mode mask	(umask)

     +o	BSD login class

     +o	scheduling priority (aka nice value)

   Process model
     There are two distinct ways sudo can run a	command.

     If	an I/O logging plugin is configured or if the security policy explic-
     itly requests it, a new pseudo-terminal ("pty") is	allocated and fork(2)
     is	used to	create a second	sudo process, referred to as the monitor.  The
     monitor creates a new terminal session with itself	as the leader and the
     pty as its	controlling terminal, calls fork(2), sets up the execution en-
     vironment as described above, and then uses the execve(2) system call to
     run the command in	the child process.  The	monitor	exists to relay	job
     control signals between the user's	existing terminal and the pty the com-
     mand is being run in.  This makes it possible to suspend and resume the
     command.  Without the monitor, the	command	would be in what POSIX terms
     an	"orphaned process group" and it	would not receive any job control sig-
     nals from the kernel.  When the command exits or is terminated by a sig-
     nal, the monitor passes the command's exit	status to the main sudo
     process and exits.	 After receiving the command's exit status, the	main
     sudo passes the command's exit status to the security policy's close
     function and exits.

     If	no pty is used,	sudo calls fork(2), sets up the	execution environment
     as	described above, and uses the execve(2)	system call to run the command
     in	the child process.  The	main sudo process waits	until the command has
     completed,	then passes the	command's exit status to the security policy's
     close function and	exits.	As a special case, if the policy plugin	does
     not define	a close	function, sudo will execute the	command	directly in-
     stead of calling fork(2) first.  The sudoers policy plugin	will only de-
     fine a close function when	I/O logging is enabled,	a pty is required, or
     the pam_session or	pam_setcred options are	enabled.  Note that
     pam_session and pam_setcred are enabled by	default	on systems using PAM.

     On	systems	that use PAM, the security policy's close function is respon-
     sible for closing the PAM session.	 It may	also log the command's exit
     status.

   Signal handling
     When the command is run as	a child	of the sudo process, sudo will relay
     signals it	receives to the	command.  The SIGINT and SIGQUIT signals are
     only relayed when the command is being run	in a new pty or	when the sig-
     nal was sent by a user process, not the kernel.  This prevents the	com-
     mand from receiving SIGINT	twice each time	the user enters	control-C.
     Some signals, such	as SIGSTOP and SIGKILL,	cannot be caught and thus will
     not be relayed to the command.  As	a general rule,	SIGTSTP	should be used
     instead of	SIGSTOP	when you wish to suspend a command being run by	sudo.

     As	a special case,	sudo will not relay signals that were sent by the com-
     mand it is	running.  This prevents	the command from accidentally killing
     itself.  On some systems, the reboot(8) command sends SIGTERM to all non-
     system processes other than itself	before rebooting the system.  This
     prevents sudo from	relaying the SIGTERM signal it received	back to
     reboot(8),	which might then exit before the system	was actually rebooted,
     leaving it	in a half-dead state similar to	single user mode.  Note, how-
     ever, that	this check only	applies	to the command run by sudo and not any
     other processes that the command may create.  As a	result,	running	a
     script that calls reboot(8) or shutdown(8)	via sudo may cause the system
     to	end up in this undefined state unless the reboot(8) or shutdown(8) are
     run using the exec() family of functions instead of system() (which in-
     terposes a	shell between the command and the calling process).

     If	no I/O logging plugins are loaded and the policy plugin	has not	de-
     fined a close() function, set a command timeout or	required that the com-
     mand be run in a new pty, sudo may	execute	the command directly instead
     of	running	it as a	child process.

   Plugins
     Plugins may be specified via Plugin directives in the sudo.conf(5)	file.
     They may be loaded	as dynamic shared objects (on systems that support
     them), or compiled	directly into the sudo binary.	If no sudo.conf(5)
     file is present, or it contains no	Plugin lines, sudo will	use the	tradi-
     tional sudoers security policy and	I/O logging.  See the sudo.conf(5)
     manual for	details	of the /usr/local/etc/sudo.conf	file and the
     sudo_plugin(5) manual for more information	about the sudo plugin archi-
     tecture.

EXIT VALUE
     Upon successful execution of a command, the exit status from sudo will be
     the exit status of	the program that was executed.	If the command termi-
     nated due to receipt of a signal, sudo will send itself the same signal
     that terminated the command.

     If	the -l option was specified without a command, sudo will exit with a
     value of 0	if the user is allowed to run sudo and they authenticated suc-
     cessfully (as required by the security policy).  If a command is speci-
     fied with the -l option, the exit value will only be 0 if the command is
     permitted by the security policy, otherwise it will be 1.

     If	there is an authentication failure, a configuration/permission problem
     or	if the given command cannot be executed, sudo exits with a value of 1.
     In	the latter case, the error string is printed to	the standard error.
     If	sudo cannot stat(2) one	or more	entries	in the user's PATH, an error
     is	printed	to the standard	error.	(If the	directory does not exist or if
     it	is not really a	directory, the entry is	ignored	and no error is
     printed.)	This should not	happen under normal circumstances.  The	most
     common reason for stat(2) to return "permission denied" is	if you are
     running an	automounter and	one of the directories in your PATH is on a
     machine that is currently unreachable.

SECURITY NOTES
     sudo tries	to be safe when	executing external commands.

     To	prevent	command	spoofing, sudo checks "." and "" (both denoting	cur-
     rent directory) last when searching for a command in the user's PATH (if
     one or both are in	the PATH).  Note, however, that	the actual PATH	envi-
     ronment variable is not modified and is passed unchanged to the program
     that sudo executes.

     Users should never	be granted sudo	privileges to execute files that are
     writable by the user or that reside in a directory	that is	writable by
     the user.	If the user can	modify or replace the command there is no way
     to	limit what additional commands they can	run.

     Please note that sudo will	normally only log the command it explicitly
     runs.  If a user runs a command such as sudo su or	sudo sh, subsequent
     commands run from that shell are not subject to sudo's security policy.
     The same is true for commands that	offer shell escapes (including most
     editors).	If I/O logging is enabled, subsequent commands will have their
     input and/or output logged, but there will	not be traditional logs	for
     those commands.  Because of this, care must be taken when giving users
     access to commands	via sudo to verify that	the command does not inadver-
     tently give the user an effective root shell.  For	more information,
     please see	the Preventing shell escapes section in	sudoers(5).

     To	prevent	the disclosure of potentially sensitive	information, sudo dis-
     ables core	dumps by default while it is executing (they are re-enabled
     for the command that is run).  This historical practice dates from	a time
     when most operating systems allowed set-user-ID processes to dump core by
     default.  To aid in debugging sudo	crashes, you may wish to re-enable
     core dumps	by setting "disable_coredump" to false in the sudo.conf(5)
     file as follows:

	   Set disable_coredump	false

     See the sudo.conf(5) manual for more information.

ENVIRONMENT
     sudo utilizes the following environment variables.	 The security policy
     has control over the actual content of the	command's environment.

     EDITOR	      Default editor to	use in -e (sudoedit) mode if neither
		      SUDO_EDITOR nor VISUAL is	set.

     MAIL	      Set to the mail spool of the target user when the	-i op-
		      tion is specified	or when	env_reset is enabled in
		      sudoers (unless MAIL is present in the env_keep list).

     HOME	      Set to the home directory	of the target user when	the -i
		      or -H options are	specified, when	the -s option is spec-
		      ified and	set_home is set	in sudoers, when
		      always_set_home is enabled in sudoers, or	when env_reset
		      is enabled in sudoers and	HOME is	not present in the
		      env_keep list.

     LOGNAME	      Set to the login name of the target user when the	-i op-
		      tion is specified, when the set_logname option is	en-
		      abled in sudoers or when the env_reset option is enabled
		      in sudoers (unless LOGNAME is present in the env_keep
		      list).

     PATH	      May be overridden	by the security	policy.

     SHELL	      Used to determine	shell to run with -s option.

     SUDO_ASKPASS     Specifies	the path to a helper program used to read the
		      password if no terminal is available or if the -A	option
		      is specified.

     SUDO_COMMAND     Set to the command run by	sudo, including	command	line
		      arguments.  The command line arguments are truncated at
		      4096 characters to prevent a potential execution error.

     SUDO_EDITOR      Default editor to	use in -e (sudoedit) mode.

     SUDO_GID	      Set to the group-ID of the user who invoked sudo.

     SUDO_PROMPT      Used as the default password prompt unless the -p	option
		      was specified.

     SUDO_PS1	      If set, PS1 will be set to its value for the program be-
		      ing run.

     SUDO_UID	      Set to the user-ID of the	user who invoked sudo.

     SUDO_USER	      Set to the login name of the user	who invoked sudo.

     USER	      Set to the same value as LOGNAME,	described above.

     VISUAL	      Default editor to	use in -e (sudoedit) mode if
		      SUDO_EDITOR is not set.

FILES
     /usr/local/etc/sudo.conf  sudo front end configuration

EXAMPLES
     Note: the following examples assume a properly configured security	pol-
     icy.

     To	get a file listing of an unreadable directory:

	   $ sudo ls /usr/local/protected

     To	list the home directory	of user	yaz on a machine where the file	system
     holding ~yaz is not exported as root:

	   $ sudo -u yaz ls ~yaz

     To	edit the index.html file as user www:

	   $ sudoedit -u www ~www/htdocs/index.html

     To	view system logs only accessible to root and users in the adm group:

	   $ sudo -g adm more /var/log/syslog

     To	run an editor as jim with a different primary group:

	   $ sudoedit -u jim -g	audio ~jim/sound.txt

     To	shut down a machine:

	   $ sudo shutdown -r +15 "quick reboot"

     To	make a usage listing of	the directories	in the /home partition.	 Note
     that this runs the	commands in a sub-shell	to make	the cd and file	redi-
     rection work.

	   $ sudo sh -c	"cd /home ; du -s * | sort -rn > USAGE"

DIAGNOSTICS
     Error messages produced by	sudo include:

     editing files in a	writable directory is not permitted
	   By default, sudoedit	does not permit	editing	a file when any	of the
	   parent directories are writable by the invoking user.  This avoids
	   a race condition that could allow the user to overwrite an arbi-
	   trary file.	See the	sudoedit_checkdir option in sudoers(5) for
	   more	information.

     editing symbolic links is not permitted
	   By default, sudoedit	does not follow	symbolic links when opening
	   files.  See the sudoedit_follow option in sudoers(5)	for more in-
	   formation.

     effective uid is not 0, is	sudo installed setuid root?
	   sudo	was not	run with root privileges.  The sudo binary must	be
	   owned by the	root user and have the set-user-ID bit set.  Also, it
	   must	not be located on a file system	mounted	with the `nosuid' op-
	   tion	or on an NFS file system that maps uid 0 to an unprivileged
	   uid.

     effective uid is not 0, is	sudo on	a file system with the 'nosuid'	option
	   set or an NFS file system without root privileges?
	   sudo	was not	run with root privileges.  The sudo binary has the
	   proper owner	and permissions	but it still did not run with root
	   privileges.	The most common	reason for this	is that	the file sys-
	   tem the sudo	binary is located on is	mounted	with the `nosuid' op-
	   tion	or it is an NFS	file system that maps uid 0 to an unprivileged
	   uid.

     fatal error, unable to load plugins
	   An error occurred while loading or initializing the plugins speci-
	   fied	in sudo.conf(5).

     invalid environment variable name
	   One or more environment variable names specified via	the -E option
	   contained an	equal sign (`=').  The arguments to the	-E option
	   should be environment variable names	without	an associated value.

     no	password was provided
	   When	sudo tried to read the password, it did	not receive any	char-
	   acters.  This may happen if no terminal is available	(or the	-S op-
	   tion	is specified) and the standard input has been redirected from
	   /dev/null.

     a terminal	is required to read the	password
	   sudo	needs to read the password but there is	no mechanism available
	   for it to do	so.  A terminal	is not present to read the password
	   from, sudo has not been configured to read from the standard	input,
	   the -S option was not used, and no askpass helper has been speci-
	   fied	either via the sudo.conf(5) file or the	SUDO_ASKPASS environ-
	   ment	variable.

     no	writable temporary directory found
	   sudoedit was	unable to find a usable	temporary directory in which
	   to store its	intermediate files.

     sudo must be owned	by uid 0 and have the setuid bit set
	   sudo	was not	run with root privileges.  The sudo binary does	not
	   have	the correct owner or permissions.  It must be owned by the
	   root	user and have the set-user-ID bit set.

     sudoedit is not supported on this platform
	   It is only possible to run sudoedit on systems that support setting
	   the effective user-ID.

     timed out reading password
	   The user did	not enter a password before the	password timeout (5
	   minutes by default) expired.

     you do not	exist in the passwd database
	   Your	user-ID	does not appear	in the system passwd database.

     you may not specify environment variables in edit mode
	   It is only possible to specify environment variables	when running a
	   command.  When editing a file, the editor is	run with the user's
	   environment unmodified.

SEE ALSO
     su(1), stat(2), login_cap(3), passwd(5), sudo.conf(5), sudo_plugin(5),
     sudoers(5), sudoers_timestamp(5), sudoreplay(8), visudo(8)

HISTORY
     See the HISTORY file in the sudo distribution (https://www.sudo.ws/his-
     tory.html)	for a brief history of sudo.

AUTHORS
     Many people have worked on	sudo over the years; this version consists of
     code written primarily by:

	   Todd	C. Miller

     See the CONTRIBUTORS file in the sudo distribution
     (https://www.sudo.ws/contributors.html) for an exhaustive list of people
     who have contributed to sudo.

CAVEATS
     There is no easy way to prevent a user from gaining a root	shell if that
     user is allowed to	run arbitrary commands via sudo.  Also,	many programs
     (such as editors) allow the user to run commands via shell	escapes, thus
     avoiding sudo's checks.  However, on most systems it is possible to pre-
     vent shell	escapes	with the sudoers(5) plugin's noexec functionality.

     It	is not meaningful to run the cd	command	directly via sudo, e.g.,

	   $ sudo cd /usr/local/protected

     since when	the command exits the parent process (your shell) will still
     be	the same.  Please see the EXAMPLES section for more information.

     Running shell scripts via sudo can	expose the same	kernel bugs that make
     set-user-ID shell scripts unsafe on some operating	systems	(if your OS
     has a /dev/fd/ directory, set-user-ID shell scripts are generally safe).

BUGS
     If	you feel you have found	a bug in sudo, please submit a bug report at
     https://bugzilla.sudo.ws/

SUPPORT
     Limited free support is available via the sudo-users mailing list,	see
     https://www.sudo.ws/mailman/listinfo/sudo-users to	subscribe or search
     the archives.

DISCLAIMER
     sudo is provided "AS IS" and any express or implied warranties, includ-
     ing, but not limited to, the implied warranties of	merchantability	and
     fitness for a particular purpose are disclaimed.  See the LICENSE file
     distributed with sudo or https://www.sudo.ws/license.html for complete
     details.

Sudo 1.9.2			  May 7, 2020			    Sudo 1.9.2

NAME | SYNOPSIS | DESCRIPTION | COMMAND EXECUTION | EXIT VALUE | SECURITY NOTES | ENVIRONMENT | FILES | EXAMPLES | DIAGNOSTICS | SEE ALSO | HISTORY | AUTHORS | CAVEATS | BUGS | SUPPORT | DISCLAIMER

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