The actual size of the built-in integral types are machine dependent (see also the Tip Standards Provide Guarantees Regarding the Sizes of Integral Types):

 //built-in integral types with machine-dependent sizeschar int short long 

When you need explicit, platform-independent sizes, you can use the following standardized typedef’s instead:

 int8  //signed 8 bitsint16 int32 

These typedef’s are defined in the standard header for C and for C++. Many platforms also define int64. Unsigned versions of these typedef’s exist as well:

 uint8  //unsigned 8 bitsuint16 uint32