为什么 GetSystemInfo().minimumApplicationAddress 返回的数字大于 GetSystemInfo().maximumApplicationAddress？答案

【问题标题】：Why does GetSystemInfo().minimumApplicationAddress return a number greater than GetSystemInfo().maximumApplicationAddress?为什么 GetSystemInfo().minimumApplicationAddress 返回的数字大于 GetSystemInfo().maximumApplicationAddress？
【发布时间】：2019-12-09 05:04:35
【问题描述】：

我正在关注如何操作内存的教程，无论出于何种原因，以下代码给出了 65536 的 minimumAddress 和 -65537 的最大地址，这没有多大意义。

我希望最大地址大于最小值，否则意味着没有地址。

Here 是指向我正在关注的教程的链接，以防万一。

SYSTEM_INFO sys_info = new SYSTEM_INFO();
GetSystemInfo(out sys_info);

IntPtr proc_min_address = sys_info.minimumApplicationAddress;
IntPtr proc_max_address = sys_info.maximumApplicationAddress;

// saving the values as long ints so I won't have to do a lot of casts later

long proc_min_address_l = (long)proc_min_address;
long proc_max_address_l = (long)proc_max_address;

Console.WriteLine("Min Addr: {0}, Max Addr: {1}", proc_min_address_l, proc_max_address_l);

【问题讨论】：

我无法重现此问题，最小地址为 65536，最大地址为 140737488289791
这可能是一个错误还是 Windows 的一些安全锁？

标签： c# memory

【解决方案1】：

sys_info.maximumApplicationAddress 因平台类型而异：
任何 CPU：0xffffffff
x64: 0x00007ffffffffff
x86: 0x7ffeffff

当进行长转换时，您将转换为 0xfffeffff 的 4 字节有符号值 (int32)，即 -65537。

由于使用内存地址，因此不会有任何负值，因此您可以更改为无符号值。

IntPtr 到 UIntPtr

长到乌龙

public struct SYSTEM_INFO
{
...
    public UIntPtr minimumApplicationAddress;
    public UIntPtr maximumApplicationAddress;
...
}

public static void Main()
{
    SYSTEM_INFO sys_info = new SYSTEM_INFO();
    GetSystemInfo(out sys_info);

    UIntPtr proc_min_address = sys_info.minimumApplicationAddress;
    UIntPtr proc_max_address = sys_info.maximumApplicationAddress;

    // saving the values as ulong ints so I won't have to do a lot of casts later

    ulong proc_min_address_l = (ulong)proc_min_address;
    ulong proc_max_address_l = (ulong)proc_max_address;

    Console.WriteLine("Min Addr: {0}, Max Addr: {1}", proc_min_address_l, proc_max_address_l);
}

【讨论】：