Importing a DLL Function into Go using DllImport Equivalent

Problem Statement

In C#, DllImport is used to import functions from a DLL written in C. Is there a similar mechanism available in Go that allows for importing DLL functions created in C?

Solution Using CGO and Syscall

There are multiple approaches to import a DLL function into Go. One method involves using the cgo package, which facilitates the creation of Go bindings for C code. With cgo, you can directly call DLL functions as if they were Go functions.

Another method leverages the syscall package. This allows you to interact with the system's low-level APIs, including DLL loading and function calling. By explicitly managing memory and calling the necessary system functions, you can import DLL functions using syscall.

Example Code for CGO

import "C"

func main() {
    C.SomeDllFunc(...)
}

Example Code for Syscall

import (
    "fmt"
    "syscall"
    "unsafe"
)

func main() {
    kernel32, _ := syscall.LoadLibrary("kernel32.dll")
    getModuleHandle, _ := syscall.GetProcAddress(kernel32, "GetModuleHandleW")

    handle := GetModuleHandle()
    fmt.Println(handle)
}

func GetModuleHandle() uintptr {
    var nargs uintptr = 0
    ret, _, _ := syscall.Syscall(uintptr(getModuleHandle), nargs, 0, 0, 0)
    return ret
}

Additional Resources

For further details, refer to the following resources:

• [Using DLLs on Windows](https://github.com/golang/go/wiki/WindowsDLLs)