如何P/调用os_log? [英] How to P/Invoke os_log?

问题描述

在.NET Core控制台应用程序中从C#调用MacOS的os_log的语法应该是什么??

基于
https://developer.apple.com/documentation/os/os_log
和
如何在Xamarin中使用iOS OSLog?
和
https://opensource. apple.com/source/xnu/xnu-4903.221.2/libkern/os/log.h.auto.html
我期待这样的事情:

Based on
https://developer.apple.com/documentation/os/os_log
and
How to use iOS OSLog with Xamarin?
and
https://opensource.apple.com/source/xnu/xnu-4903.221.2/libkern/os/log.h.auto.html
I was expecting something like this:

using System.Runtime.InteropServices;

namespace Foo 
{
 class Program
 {
  [DllImport("__Internal", EntryPoint = "os_log_create")]
  private static extern IntPtr os_log_create(string subsystem, string category);

  [DllImport("__Internal", EntryPoint = "os_log")]
  private static extern void os_log(IntPtr log, string format, string message);

  static void Main(string[] args)
  {  
   IntPtr log = os_log_create("some.bundle.id", "SomeCategory");
   os_log(log, "%s", "Test!");
  }
 }
}

但是，当我尝试在Mac上运行此程序时，会得到一个System.DllNotFoundException，其内容为Unable to load shared library '__Internal' or one of its dependencies....

However, when I try to run this on my Mac I get a System.DllNotFoundException that says Unable to load shared library '__Internal' or one of its dependencies... .

任何有关此问题或C#和MacOS之间的P/Invoke的帮助都将非常有帮助，谢谢！

Any help with this issue or P/Invoke between C# and MacOS would be very helpful, thanks!

推荐答案

宏os_log

与os_log_create函数相比，os_log是一个宏，如注释中所述.

In contrast to the os_log_create function, os_log is a macro, as already mentioned in the comments.

因此，如果您要用C编写:

So if you would write in C:

os_log(log, "%{public}s", "Test!");

它最终将调用一个名为_os_log_impl的函数，但该函数的第一个参数将是指针__dso_handle，我们无法从托管端访问该指针.

It would finally call a function named _os_log_impl, but the first parameter of that would be a pointer __dso_handle to which we don't have access from the managed side.

可能的解决方案

但是，如果没有Apple的新日志记录系统，您不必做任何事情.一种可能性是创建一个动态库，该库提供可从托管C#代码轻松调用的已定义API.

But you don't have to do without the new logging system from Apple. One possibility is to create a dynamic library that provides a defined API that can easily be called from the managed C# code.

如何在Xcode中创建动态库

在Xcode中创建动态库很容易:

It is easy to create a dynamic library in Xcode:

• 选择XCode< File/New Project>

• choose in XCode <File/New Project>

在 macOS 部分

使用类型动态

最小示例

我们自己的 Logging 库的最小.c示例如下所示:

A minimal .c example for our own Logging library might look like this:

 #include <os/log.h>

 extern void Log(os_log_t log, char *message) {
     os_log(log, "%{public}s", message);
 }

从.Net拨打电话

我拿走了你的资料，只是对其做了些微修改:

I took your source and only slightly modified it:

using System;
using System.Runtime.InteropServices;

namespace Foo 
{
    class Program
    {
        [DllImport("System", EntryPoint = "os_log_create")]
        private static extern IntPtr os_log_create(string subsystem, string category);

        [DllImport("Logging", EntryPoint = "Log")]
        private static extern void Log(IntPtr log, string msg);

        static void Main(string[] args)
        {  
            IntPtr log = os_log_create("some.bundle.id", "SomeCategory");
            Log(log, "Test!");
        }
    }
}

使用Xcode创建的动态库的名称为 Logging .我们在C中创建的日志记录功能在此处名为 Log .

The dynamic library created with Xcode has the name Logging. Our in C created logging function is named Log here.

当然，您可以根据需要设计API，这应该是一个尽可能接近问题的最小示例.

Of course you can design the API as comfortable as you want, this should be a minimal example that is as close to the question as possible.

控制台实用程序中的输出

控制台实用程序中的输出(如果您过滤 some.bundle.id )将如下所示:

The output in the Console utility (if you filter for some.bundle.id) would look like this:

这篇关于如何P/调用os_log?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！