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alvas
Asked: 2013-10-08 04:52:53 +0800 CST

Is there a single line command to do `su`?

  • 772

I can do an su with su <username> and it asks for my password. Is there a password parameter for su such that i wont be prompted for a password?

e.g. su <username> -p <password>

password

3 Answers

  1. If you want to write a script that runs as a different user something like this works, though it dows output the word "password" without a newline to standard out

    su - username <<!
enterpasswordhere
enter commands to run as the new user
!

    if you have a user named fred with a password of 1234 and want to get an ls of fred's home directory as fred, without the password string displayed, it would look like

    su - fred <<! >/dev/null 2>&1
1234
whoami > /dev/tty
ls > /dev/tty
!
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  2. I belive, there is not and it would not be a good idea. Here's why:
    If you write a password in a command like su <username> -p <password>, it would be stored in plain text in your bash history. This is certainly a huge security issue.

    If you need to run commands with su (or sudo) in an automated way, write a shellscript containig the commands without su or sudo and run su <username> script.sh

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  3. If you want to execute some specific commands as a new user, use the following command:
    sudo -u {username} {command to be executed as the new user}

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