This post is older than a year. Consider some information might not be accurate anymore.
http://permissions-calculator.org/ is a nice web application, to calculate octal permissions for chmod.
- The basic chmod command allows the change the access rights for
user + group + others.
- The numeric computation consists of 2^2=4, 2^1=2, 2^0=1 = rwx
The current permission scheme in numeric and symbolic values:
|7||read, write and execute (4 + 2 + 1 = 7)||`rwx`|
|6||read and write (4 + 2 = 6)||`rw-`|
|5||read and execute (4 + 1 = 5)||`r-x`|
|3||write and execute||`-wx`|