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I was wondering how to run a command as another user from a script.
I have the script's owner set as root. I also have the following command being run within the script to run the command as the hudson user:
su -c command hudson
Is this the correct syntax?
Yes. Here's the --help:
$ su --help
Usage: su [options] [LOGIN]
Options:
-c, --command COMMAND pass COMMAND to the invoked shell
-h, --help display this help message and exit
-, -l, --login make the shell a login shell
-m, -p,
--preserve-environment do not reset environment variables, and
keep the same shell
-s, --shell SHELL use SHELL instead of the default in passwd
And some testing (I used sudo as I don't know the password for the nobody account)
$ sudo su -c whoami nobody
[sudo] password for oli:
nobody
When your command takes arguments you need to quote it. If you don't, strange things will occur. Here I am —as root— trying to create a directory in /home/oli (as oli) without quoting the full command:
# su -c mkdir /home/oli/java oli
No passwd entry for user '/home/oli/java'
It's only read mkdir as the value for the -c flag and it's trying to use /home/oli/java as the username. If we quote it, it just works:
# su -c "mkdir /home/oli/java" oli
# stat /home/oli/java
File: ‘/home/oli/java’
Size: 4096 Blocks: 8 IO Block: 4096 directory
Device: 811h/2065d Inode: 5817025 Links: 2
Access: (0775/drwxrwxr-x) Uid: ( 1000/ oli) Gid: ( 1000/ oli)
Access: 2016-02-16 10:49:15.467375905 +0000
Modify: 2016-02-16 10:49:15.467375905 +0000
Change: 2016-02-16 10:49:15.467375905 +0000
Birth: -
-c option, does su invoke a shell and execute the command in the shell? Or does it execute the command without additional shell?
Note: "I have the script's owner set as root" doesn't do anything; even if you have the setuid bit set it still doesn't work
Assuming you're actually running the script as root, however, you can use sudo. su is primarily for switching users, while sudo is for executing commands as other users. The -u flag lets you specify which user to execute the command as:
sudo -u hudson command
sudo you can just get this: root is not in the sudoers file. Which makes su - <username> -c "command to run" the only option.
sudo -u kilgore mv this that)
May 23, 2019 at 21:10
sudo cat /etc/passwd | grep user-abc. If you see something like this:user-abc:x:994:994::/home/user-abc:/bin/falsethen it won't work. That's because the last part "/bin/false" means that there is no shell for that user.