chmod-Octal numerical permission for linux
/binary table
r,w,x binary octal
--- 000 0
--x 001 1
-w- 010 2
-wx 011 3
r-- 100 4
r-x 101 5
rw- 110 6
rwx 111 7
nobody has permission
chmod 000 file
u+r g+rx o+rx
chmod 755 file
/binary table
r,w,x binary octal
--- 000 0
--x 001 1
-w- 010 2
-wx 011 3
r-- 100 4
r-x 101 5
rw- 110 6
rwx 111 7
nobody has permission
chmod 000 file
u+r g+rx o+rx
chmod 755 file