In Python's stat module, when I print stat.S_IRWXU | stat.S_IRWXG | stat.S_IRWXO, why do I get 511 instead of 777?

Question

The octal integer to set all permissions as active is 0777. Then why do I get 511 when I print the string values of the same?

Answer 1

0777 is an octal representation.

In other word, 0777 = 7 * (8**2) + 7 * (8**1) + 7 * (8**0)

>>> 0777
511
>>> 7 * (8**2) + 7 * (8**1) + 7 * (8**0)
511

>>> 0777 == 777
False

---

If you want to get octal representation of a number, use oct, % operator or str.foramt with appropriate format specifier:

>>> oct(511)
'0777'
>>> '%o' % 511
'777'
>>> '{:o}'.format(511)
'777'