C++ Primer Plus

A Few Common Bitwise Operator Techniques

Often controlling hardware involves turning particular bits on or off or checking their status. The bitwise operators provide the means to perform such actions. We’ll go through the methods quickly.

In the following examples, lottabits represents a general value, and bit represents the value corresponding to a particular bit. Bits are numbered from right to left, beginning with bit 0, so the value corresponding to bit position n is 2ⁿ. For example, an integer with only bit number 3 set to 1 has the value 2³ or 8. In general, each individual bit corresponds to a power of 2, as described for binary numbers in Appendix A. So we’ll use the term bit to represent a power of 2; this corresponds to a particular ...