The number of bits in a byte is specified by the CHAR_BIT macro, which is required to be at least 8. It's commonly larger than 8 on C compilers for some DSPs, b

The number of bits in a byte is specified by the CHAR_BIT macro, which is required to be at least 8. It's commonly larger than 8 on C compilers for some DSPs, but almost universally 8 for hosted implementations. POSIX specifically requires it to be exactly 8.