Chapter 3, page 101. File modes.
In the text the auther says,
"Values for each digit are ANDed together; do digit 2 will have 2 & 1, giving 3."
Now, I'm not an amazing hacker, but even I know that is completely wrong.
int n = 2&1;
printf( "2 & 1 = %d", n );
Will print:
2 & 1 = 0
10 AND 01 = 00
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