Specifying the bits in position 1 is optional. For position 1, you can specify these octal numbers:

0

Off

1

Sticky bit on

2

Set-group-ID-on execution

3

Set-group-ID-on execution and set the sticky bit on

4

Set-user-ID on execution

5

Set-user-ID on execution and set the sticky bit on

6

Set-user-ID and set-group-ID on execution

7

Set-user-ID and set-group-ID on execution and set the sticky bit on