C查询内存大小

int GetMemory(void)
{

    MEMORYSTATUSEX statex;
    statex.dwLength = sizeof (statex);
    GlobalMemoryStatusEx (&statex);
    int mem = statex.ullTotalPhys/1024/1024/1000;
    //printf("%d G",statex.ullTotalPhys/1024/1024/1000);//现实内存大小
    return mem;
}