在使用 dotnet 8.0 創建一個 C# console app后，執行完編譯操作，會發現除了生成可執行文件外，還生成一個 dll文件。

 $ls
ConsoleApp1            ConsoleApp1.dll  ConsoleApp1.runtimeconfig.json
ConsoleApp1.deps.json  ConsoleApp1.pdb

 $ file ConsoleApp1
ConsoleApp1: ELF 64-bit LSB pie executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, for GNU/Linux 3.2.0, BuildID[sha1]=bf7702fd9cd2edf0452d7e804bf305b1ea8b0f21, stripped
$ file ConsoleApp1.dll 
ConsoleApp1.dll: PE32 executable (console) Intel 80386 Mono/.Net assembly, for MS Windows, 3 sections

可執行文件是一個app host, 它是一個native binary； dll文件則是一個 managed app, 可以用 dotnet ConsoleApp1.dll 執行。執行 可執行文件的時候，內部會調用 dll.

$ ./ConsoleApp1 
hello, world
$ dotnet ConsoleApp1.dll 
hello, world

?如果按照如下的方式執行，則會輸出一個執行加載過程的日志文件：

$ COREHOST_TRACE=1 COREHOST_TRACEFILE=out.txt ./ConsoleApp1

日志文件開頭的一部分如下：

Tracing enabled @ Wed Jul  9 16:16:59 2025 GMT
--- Invoked apphost [version: 8.0.17 @Commit: 77545d6fd5ca79bc08198fd6d8037c14843f14ad] main = {
./ConsoleApp1
}
The managed DLL bound to this executable is: 'ConsoleApp1.dll'
Looking for architecture-specific install_location file in '/etc/dotnet/install_location_x64'.
Found registered install location '/usr/lib/dotnet'.
Using global installation location [/usr/lib/dotnet] as runtime location.
Reading fx resolver directory=[/usr/lib/dotnet/host/fxr]
Considering fxr version=[8.0.17]...
Detected latest fxr version=[/usr/lib/dotnet/host/fxr/8.0.17]...
Resolved fxr [/usr/lib/dotnet/host/fxr/8.0.17/libhostfxr.so]...
Invoking fx resolver [/usr/lib/dotnet/host/fxr/8.0.17/libhostfxr.so] hostfxr_main_startupinfo

參考：

Anatomy of a .NET app

How the dotnet CLI tooling runs your code · Performance is a Feature!