SYNOPSIS
        int test_bit(string str, int n)

DESCRIPTION
        Return 0 or 1 of bit n was set in string str.

        Each character contains 6 bits. So you can store a value
        between 0 and 63 in one character (2^6=64). Starting character
        is the blank " " which has the value 0. The first character in
        the string is the one with the lowest bits (0-5).

EXAMPLES
        test_bit("_",5);

        Returns 1 because "_" stands for the number 63 and therefore
        the 6th bit is set.

        test_bit(" ",3);

        Returns 0 because " " stands for 0 and no bit is set.

SEE ALSO
        set_bit(E), clear_bit(E), last_bit(E), next_bit(E), count_bits(E),
        and_bits(E), or_bits(E), xor_bits(E), invert_bits(E), copy_bits(E)