ntdll/version.c

#include <windows.h>
#include <nt.h>

long int __stdcall RtlGetVersion(RTL_OSVERSIONINFO *VersionInformation) {
	PROCESS_BASIC_INFORMATION pbi;
	long int r = NtQueryInformationProcess((void *)-1, ProcessBasicInformation, &pbi, sizeof pbi, NULL);
	if(r < 0) return r;
	PEB *peb = pbi.PebBaseAddress;
	VersionInformation->dwMajorVersion = peb->OSMajorVersion;
	VersionInformation->dwMinorVersion = peb->OSMinorVersion;
	VersionInformation->dwBuildNumber  = peb->OSBuildNumber;
	VersionInformation->dwPlatformId   = peb->OSPlatformId;
	return 0;
}