Understanding the sizes of data types

As discussed earlier, the number of bytes that a type uses is directly related to the range of values it can hold. Up to this point, this has all been necessarily theoretical. Now, let's write a program to demonstrate what we've been exploring.

While we are focusing exclusively on the C standard, we need to be aware that the standard allows for quite a bit of discretion on the part of any compiler implementor. This is necessary because not all CPUs have the same architecture, nor do they all have the same capabilities. Nor should they. Also, compilers are implemented by humans trying to interpret complex standards documents. Humans, despite our best intentions, might not perfectly conform to the standard.

In this light, it is critical to understand the behavior of your compiler on your system. Here and throughout the book, we emphasize the trust but verify principle so that we are not surprised when things do not work as we expect...