__int8, __int16, __int32, __int64
Microsoft-specific
Microsoft C/C++ features support for sized integer types. You can declare 8-, 16-, 32-, or 64-bit integer variables by using the __intN type specifier, where N is 8, 16, 32, or 64.
The following example declares one variable for each of these types of sized integers:
__int8 nSmall; // Declares 8-bit integer
__int16 nMedium; // Declares 16-bit integer
__int32 nLarge; // Declares 32-bit integer
__int64 nHuge; // Declares 64-bit integer
The types __int8, __int16, and __int32 are synonyms for the ANSI types that have the same size, and are useful for writing portable code that behaves identically across multiple platforms. The __int8 data type is synonymous with type char, __int16 is synonymous with type short, and __int32 is synonymous with type int. The __int64 type is synonymous with type long long.
For compatibility with previous versions, _int8, _int16, _int32, and _int64 are synonyms for __int8, __int16, __int32, and __int64 unless compiler option /Za (Disable language extensions) is specified.
Example
The following sample shows that an __intN parameter will be promoted to int:
// sized_int_types.cpp
#include <stdio.h>
void func(int i) {
printf_s("%s\n", __FUNCTION__);
}
int main()
{
__int8 i8 = 100;
func(i8); // no void func(__int8 i8) function
// __int8 will be promoted to int
}
func