Creating Shared DLL with Go Lang

[Evandson_Dantas]

I have to create a DLL with variable and functions exposed.
The C code that do it is:

#include <stdio.h>

double In = 1.0;
double Out = 0.0;
double G = 2;

void step() {
    Out = G * In;
}

and compile command: gcc -shared -o root.dll example.c

Where other system get value based on memory address.

I want to create the same using Golang, but //export didnt generate readable dll method. Can someone give me a tip how can i do that?

[Modestying (MIMO431)]

try go build -buildmode=c-shared -o example.dll .

[Evandson_Dantas]

thanks MIMO431.

Its create the DLL but not exported method or variable is available.

Check the following comparative:

[Evandson_Dantas]

Golang can only export functions. To it, is required to use CGO, captalized function and comments to export, like:

//export <Name_of_function>
func <Name_of_function>(...){...}

Sample code:

package main

import "C"

// Global variables
var (
	In  float64 = 1.0
	Out float64 = 0.0
	G   float64 = 2.0
)

//export Step
func Step() {
	Out = G * In
}

//export GetIn
func GetIn() float64 {
	return In
}

//export SetIn
func SetIn(value float64) {
	In = value
}

//export GetOut
func GetOut() float64 {
	return Out
}

//export GetG
func GetG() float64 {
	return G
}

//export SetG
func SetG(value float64) {
	G = value
}

func main() {
	// This is required for main in shared libraries, but won’t be executed when called from C
}

Which will result in:

It should be generated by @Modestying sample command:

go build -buildmode=c-shared -o example.dll .