Datasheet

686
Working with Files
password. If you don’t know what the password is, you probably shouldn’t
be using sudo. Your computer’s administrator should have given you an
appropriate password to use. After you enter the correct password, the
command executes as desired.
In case you’re curious, sudo stands for set user and do. It sets the user to the
one that you specify and performs the command that follows the username.
sudo cp ~/Desktop/MyDocument /Users/fuadramses/Desktop/MyDocument
Password:
A close cousin to the cp (copy) command is the mv (move) command. As
you can probably guess, the mv command moves a folder or file from one
location to another. (I told you that all this character-based stuff would start
to make sense, didn’t I?) To demonstrate, this command moves MyDocument
from the Desktop folder to the current user’s Home folder:
mv ~/Desktop/MyDocument ~/MyDocument
Ah, but here’s the hidden surprise: The mv command also functions as
a rename command. For instance, to rename a file MyDocument on the
Desktop to MyNewDocument, do this:
mv ~/Desktop/MyDocument ~/Desktop/MyNewDocument
Because both folders in this example reside in the same folder (~/Desktop/),
it appears as though the mv command has renamed the file.
Again, like the cp command, the mv command requires that you have proper
permissions for the action that you want to perform. Use the sudo com-
mand to perform any commands that your current user (as displayed in the
prompt) isn’t allowed to execute. On UNIX systems, not all users are neces-
sarily equal. Some users can perform functions that others can’t. This is
handy for keeping your child’s mitts off important files on your computer.
It also creates a hurdle should you choose to work on files while using your
child’s restricted user account. The sudo command lets you temporarily
become another user — presumably one that has permission to perform
some function that the current user can’t.
What would file manipulation be without the ability to delete files? Never
fear; UNIX can delete anything that you throw at it. Use the rm (short for
remove) or rmdir (short for remove directory) command to delete a folder
or file. For example, to delete MyNewDocument from the Desktop folder,
execute the rm command like this:
rm ~/Desktop/MyNewDocument
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