In last week’s article, I mentioned a special command that requires a password to perform certain tasks. This week I’d like to talk about that command a little. It is called sudo. It is both an acronym for the expression “Super User DO” and also the “su” and “do” commands put together.
The first part, “su”, is the power part. It enables you to enter commands as what is known as the “superuser” or “root” user. The superuser can do anything, which is both powerful and dangerous. When you enable as a superuser you will be warned up front that you are now capable of destroying your system with ease. While you are always required to enter your password when enabling as a superuser, you only get the warning once. After that, they assume you are on board with being responsible for your system. The warning is pretty dry in current incarnations of the OS, but in the past the text looked like this:
We trust you have received the usual lecture from the local System Administrator. It usually boils down to these two things:
- Respect the privacy of others.
- Think before you type.
Kind of friendly and humorous. (And, kind of sad that level of humor has made way for more straightforward notices.)
On to the second part: “do” is what it seems like. It is an action command. So together, you get “sudo” or SuperUserDO. One might ask why bother to use “sudo” when you could just use “su” and then type in your commands? From a caution point of view, “sudo” provides some benefits — it times out after 15 minutes, after which it requires you to enter your password again. So it’s OK to walk away and forget you were logged in as the root user, because after 15 minutes you revert to your normal status.
The “sudo” command is a great tool to accomplish tasks normally not allowed in terminal, such as changing permissions and ownership of certain files and moving things you normally couldn’t. For more information, click here to see the wikipedia page. Next week we’ll look at some tasks that require the use of this powerful command.