Learning Chmod Permissions in 30 Seconds
Scary about “drwxr-xr-x”?
Don’t worry, in 30 seconds you’ll be able to read it!
Chmod always contains three groups, the first is (u)ser, then (g)roup and finally (o)ther (public)
-|rw-|r--|r-x
 | 1 | 2 | 3
 | u | g | o
- (u)ser: user can (r)ead and (w)rite
- (g)roup: user in this same group can (r)ead.
- (o)thers/public: can (r)ead and e(x)ecute.
U = User            (1)
G = Group           (2)
O = Other (Public)  (3)
R = Read
W = Write
X = Execute
Give permisions:
chmod ugo+rwx hey.txt
This add permissions to (u)ser, (g)roup and (o)ther to (r)ead, (w)rite and e(x)ecute file hey.txt.
chmod o-r hey.txt
This remove permision for (o)ther to (r)ead.
Meaning
Now you can read what means “-rwxr-xr--”.
Yes! It’s.
- (u)ser can (r)ead, (w)rite and e(x)ecute.
- (g)rupe can (r)ead and e(x)ecute.
- (o)ther can only (r)ead.
Remeber: -rwx|r-x|r--
Linux have always 3 groups : (u)ser, (g)rups, (o)ther!
- You can give access to u,gando.
- You can give access to (r)ead, (w)rite, and e(x)ecute.
You gave access by adding plus sign (+)
- you gave ( - u)ser access to (- r)ead and (- w)rite to file hello.- chmod u+rw hello
- you remove ( - u)ser access to (- r)ead and (- w)rite to file hello.- chmod u-rw hello
—
drwxr-xr-x
first letter are type of file.
d = directory.
That’s it.