symbolic style permissions in Linux

Question

Can someone explain to me how symbolic style permissions work in Linux? And help me set the permissions of r--r-x-wx in symbolic style on a file?

Thanks

Answer 1

Permissions are mapped as follows:

r <-> 4
w <-> 2
x <-> 1

So, if you want the owner to have r, the group to have r+x and others to have w+x (even if it sounds weird), you need to use:

chmod 453 file

If you want to use the letter format, you just use what you see on screen:

chmod u=r,g=rx,o=wx file