Change Symbolic Permissions

Using r, w, and x to represent read, write, and execute permissions is called the symbolic mode of permissions representation, and the command that changes permissions is chmod. You add and remove permissions by using a combination of +, -, and the symbols r, w, and x.

For example, if you want to add execute permissions to the file mtgnotes, you would use the command:

chmod +x mtgnotes

The above command grants execute permissions to everyone: user (owner), group, and other. If you just want to grant permissions to the user and group, the command would be:

chmod ug+x mtgnotes

NOTE: u = user, g = group, o = other

Whatever goes before the plus or minus sign is the level of permission, and whatever goes after is the type of permission. For example, if you want to remove the execute permission for group, the command would be:

chmod g-x mtgnotes

Finally, you can also use multiple types of permissions in the command. To grant read, write, and execute permissions to user and group, the command would be:

chmod ug+rwx mtgnotes

Continue to the next page to check your understanding.