You in this video, I'll
tell you about Linux permissions.
Now, permissions come in three different sets.
There are basic permissions. These are the most important, so make sure you understand
them. There's also advanced permissions and access control lists. They are not as important.
The base permissions determine what the user can do on a file and you can set them on files.
Or even better, on directories.
There is the read permission with the octal value of 4.
An octal value is a value that consists of 3 bits and you can address from 0 up to 7
and these octal values are used to work with the permissions in the CHMOT command as we will see later.
And read has the octal value of 4.
The meaning on files is that if you have read, you can read contents. Basically you can open the file.
On directories, you can list the contents of directories with the LS command.
Then there is write which allows you to modify file contents, and on directories it allows you to add and remove files.
And there is execute with the octal value of one, which is required on files if you want to
run the file, if it contains executable code. And on directories it allows you to change into the directory.
Using the cd.
Execute on directories may sound a little bit odd.
The only thing to remember is that on directories you always need execute without execute. You can't do anything
on a directory, so just read on a directory doesn't work. Make sure you have read and execute.
In the next video I'll show you how to work with these.