In later C99 version of the C programming language, a
long long type is supported that doubles the capacity of the standard long to 64 bits. This type is not supported by compilers that require C code to be C++ ISO compliant, because the long long type does not currently exist in C++ (it is defined in the new, yet unfinished, C++ standard, C++0x). For an ANSI/ISO compliant compiler the minimum requirements for the specified ranges must be fulfilled; however, extending this range is permitted.[1] [2] This can be an issue when exchanging code and data between platforms, or doing direct hardware access. Thus, there are several sets of headers providing platform independent exact width types. The C standard library provides stdint.h; this was introduced in C99.
