Run command as Linux "system" user (shell = /bin/false)

Question

I created a "system" user in Ubuntu 11.04 (adduser --system) for running certain cron jobs, but sometimes I want to test things out by manually running commands as that user. What's the easiest way to do this?

su doesn't work, because the user has /bin/false as its shell (which is fine for cron). I've been manually changing the shell to /bin/bash to do my testing and then changing it back again, but I wonder is there an easier way?

Solution 1

I use su - targetuser -s /bin/bash from a root shell.

For direct command execution use -c:

su - targetuser -s /bin/bash -c "/bin/echo hello world" 

Solution 2

Use sudo. This will work even if the user doesn't have a real shell.

Comments

[ceyko]

That works, thanks! How did I miss the -s option?

[dmourati]

you can also tack on a -c "your_command_here" option to pass the command you'd like to run versus waiting for the shell and then typing it at a new prompt.