1RUNUSER(1) User Commands RUNUSER(1)
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6 runuser - run a command with substitute user and group ID
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9 runuser [options] -u user [[--] command [argument...]]
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11 runuser [options] [-] [user [argument...]]
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14 runuser can be used to run commands with a substitute user and group
15 ID. If the option -u is not given, runuser falls back to su-compatible
16 semantics and a shell is executed. The difference between the commands
17 runuser and su is that runuser does not ask for a password (because it
18 may be executed by the root user only) and it uses a different PAM
19 configuration. The command runuser does not have to be installed with
20 set-user-ID permissions.
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22 If the PAM session is not required, then the recommended solution is to
23 use the setpriv(1) command.
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25 When called without arguments, runuser defaults to running an
26 interactive shell as root.
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28 For backward compatibility, runuser defaults to not changing the
29 current directory and to setting only the environment variables HOME
30 and SHELL (plus USER and LOGNAME if the target user is not root). This
31 version of runuser uses PAM for session management.
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33 Note that runuser in all cases use PAM (pam_getenvlist()) to do the
34 final environment modification. Command-line options such as --login
35 and --preserve-environment affect the environment before it is modified
36 by PAM.
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39 -c, --command=command
40 Pass command to the shell with the -c option.
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42 -f, --fast
43 Pass -f to the shell, which may or may not be useful, depending on
44 the shell.
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46 -g, --group=group
47 The primary group to be used. This option is allowed for the root
48 user only.
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50 -G, --supp-group=group
51 Specify a supplementary group. This option is available to the root
52 user only. The first specified supplementary group is also used as
53 a primary group if the option --group is not specified.
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55 -, -l, --login
56 Start the shell as a login shell with an environment similar to a
57 real login:
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59 • clears all the environment variables except for TERM and
60 variables specified by --whitelist-environment
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62 • initializes the environment variables HOME, SHELL, USER,
63 LOGNAME, and PATH
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65 • changes to the target user’s home directory
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67 • sets argv[0] of the shell to '-' in order to make the shell a
68 login shell
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70 -P, --pty
71 Create a pseudo-terminal for the session. The independent terminal
72 provides better security as the user does not share a terminal with
73 the original session. This can be used to avoid TIOCSTI ioctl
74 terminal injection and other security attacks against terminal file
75 descriptors. The entire session can also be moved to the background
76 (e.g., runuser --pty -u username — command &). If the
77 pseudo-terminal is enabled, then runuser works as a proxy between
78 the sessions (copy stdin and stdout).
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80 This feature is mostly designed for interactive sessions. If the
81 standard input is not a terminal, but for example a pipe (e.g.,
82 echo "date" | runuser --pty -u user), then the ECHO flag for the
83 pseudo-terminal is disabled to avoid messy output.
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85 -m, -p, --preserve-environment
86 Preserve the entire environment, i.e., do not set HOME, SHELL, USER
87 or LOGNAME. The option is ignored if the option --login is
88 specified.
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90 -s, --shell=shell
91 Run the specified shell instead of the default. The shell to run is
92 selected according to the following rules, in order:
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94 • the shell specified with --shell
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96 • the shell specified in the environment variable SHELL if the
97 --preserve-environment option is used
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99 • the shell listed in the passwd entry of the target user
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101 • /bin/sh
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103 If the target user has a restricted shell (i.e., not listed in
104 /etc/shells), then the --shell option and the SHELL environment
105 variables are ignored unless the calling user is root.
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107 --session-command=command
108 Same as -c, but do not create a new session. (Discouraged.)
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110 -w, --whitelist-environment=list
111 Don’t reset the environment variables specified in the
112 comma-separated list when clearing the environment for --login. The
113 whitelist is ignored for the environment variables HOME, SHELL,
114 USER, LOGNAME, and PATH.
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116 -V, --version
117 Display version information and exit.
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119 -h, --help
120 Display help text and exit.
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123 runuser reads the /etc/default/runuser and /etc/login.defs
124 configuration files. The following configuration items are relevant for
125 runuser:
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127 ENV_PATH (string)
128 Defines the PATH environment variable for a regular user. The
129 default value is /usr/local/bin:/bin:/usr/bin.
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131 ENV_ROOTPATH (string), ENV_SUPATH (string)
132 Defines the PATH environment variable for root. ENV_SUPATH takes
133 precedence. The default value is
134 /usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin.
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136 ALWAYS_SET_PATH (boolean)
137 If set to yes and --login and --preserve-environment were not
138 specified runuser initializes PATH.
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140 The environment variable PATH may be different on systems where /bin
141 and /sbin are merged into /usr; this variable is also affected by the
142 --login command-line option and the PAM system setting (e.g.,
143 pam_env(8)).
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146 runuser normally returns the exit status of the command it executed. If
147 the command was killed by a signal, runuser returns the number of the
148 signal plus 128.
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150 Exit status generated by runuser itself:
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152 1
153 Generic error before executing the requested command
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155 126
156 The requested command could not be executed
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158 127
159 The requested command was not found
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162 /etc/pam.d/runuser
163 default PAM configuration file
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165 /etc/pam.d/runuser-l
166 PAM configuration file if --login is specified
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168 /etc/default/runuser
169 runuser specific logindef config file
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171 /etc/login.defs
172 global logindef config file
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175 This runuser command was derived from coreutils' su, which was based on
176 an implementation by David MacKenzie, and the Fedora runuser command by
177 Dan Walsh.
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180 setpriv(1), su(1), login.defs(5), shells(5), pam(8)
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183 For bug reports, use the issue tracker at
184 https://github.com/karelzak/util-linux/issues.
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187 The runuser command is part of the util-linux package which can be
188 downloaded from Linux Kernel Archive
189 <https://www.kernel.org/pub/linux/utils/util-linux/>.
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193util-linux 2.37.2 2021-06-02 RUNUSER(1)