The newly approved C99 standard defines a new header file called , which defines sets of typedef names for integer types. One of these sets defines integer types having certain exact widths:
int8_t int16_t int32_t int64_t
And their exact-width unsigned counterparts are:
uint8_t uint16_t uint32_t uint64_t
The names are rather intuitive. For example, int8_t is a signed integral type that occupies exactly eight bits. Likewise, uint8_t is an unsigned integral type that occupies exactly eight bits. Use these typedef names when you need integers whose widths are identical on every platform.