通过引用传递的参数使用P / Invoke返回垃圾

libaiousb.c

unsigned long QueryDeviceInfo(     unsigned long deviceIndex   , unsigned long *pPID   , unsigned long *pNameSize   , char *pName   , unsigned long *pDIOBytes   , unsigned long *pCounters   ){   *pPID = 9;   *pDIOBytes = 8;   *pCounters = 7;   *pNameSize = 6;   return 0;}

libaiousb.so

gcc -shared -o libaiousb.so libaiousb.c

Test.cs

using System;using System.Runtime.InteropServices;using System.Text;class Test{    [Dllimport("libaiousb")]    static extern uint QueryDeviceInfo(uint deviceIndex,        ref uint pid, ref uint nameSize, StringBuilder name,        ref uint dioBytes, ref uint counters);    static void Main()    {        uint deviceIndex = 100;        uint pid = 101;        uint nameSize = 102;        StringBuilder name = new StringBuilder("Hello World");        uint dioBytes = 103;        uint counters = 104;        uint result = QueryDeviceInfo(deviceIndex, ref pid, ref nameSize, name, ref dioBytes, ref counters);        Console.WriteLine(deviceIndex);        Console.WriteLine(pid);        Console.WriteLine(nameSize);        Console.WriteLine(dioBytes);        Console.WriteLine(counters);        Console.WriteLine(result);    }}

测试文件

gmcs Test.cs

跑：

$ mono Test.exe10096870