Using DLL from Go

In this example, GetModuleFileNameW function is called from Go code to obtain the path of running process.

GetModuleFileName function (Windows)

Retrieves the fully qualified path for the file that contains the specified module. The module must have been loaded by the current process. https://msdn.microsoft.com/en-us/library/windows/desktop/ms683197(v=vs.85).aspx

If you are not familiar with Windows API, you might confuse that what the difference between GetModuleFileName function that is documented above and GetModuleFileNameW. The suffix W means that the function receive string as UTF16 and A means that the function receives string as ASCII. GetModuleFileName function has two version, and the document above shows general description for two functions. Actually, if you did strings kernel32.dll command, you will find two functions.

$ strings kernel32.dll | grep "^GetModuleFileName.$" | sort | uniq
GetModuleFileNameA
GetModuleFileNameW

Build an executable for Windows from another OS

For example, on Mac OSX, run the following command to build an executable for windows:

$ go generate generate.go

Now syscall_windows.go is generated and you can build an executable for Windows.

$ export GOOS=windows    # It assumes GOARCH is the same between Mac OSX and Windows.
$ go build
$ file using-dll-from-go.exe
using-dll-from-go.exe: PE32+ executable for MS Windows (console) Mono/.Net assembly

Copy an executable to Windows machine and try this:

C:\>using-dll-from-go.exe
[C:\using-dll-from-go.exe]

LICENSE

MIT