main.go

// Record Windows Audio project main.go
package main

import (
	"fmt"
	"log"
	"syscall"
	"time"
	"unsafe"
)

var (
	winmm         = syscall.MustLoadDLL("winmm.dll")
	mciSendString = winmm.MustFindProc("mciSendStringW")
)

func MCIWorker(lpstrCommand string, lpstrReturnString string, uReturnLength int, hwndCallback int) uintptr {
	i, _, _ := mciSendString.Call(uintptr(unsafe.Pointer(syscall.StringToUTF16Ptr(lpstrCommand))),
		uintptr(unsafe.Pointer(syscall.StringToUTF16Ptr(lpstrReturnString))),
		uintptr(uReturnLength), uintptr(hwndCallback))
	return i
}

func main() {
	fmt.Println("winmm.dll Record Audio to .wav file")

	i := MCIWorker("open new type waveaudio alias capture", "", 0, 0)
	if i != 0 {
		log.Fatal("Error Code A: ", i)
	}

	i = MCIWorker("record capture", "", 0, 0)
	if i != 0 {
		log.Fatal("Error Code B: ", i)
	}

	fmt.Println("Listening...")

	time.Sleep(10 * time.Second)

	i = MCIWorker("save capture mic.wav", "", 0, 0)
	if i != 0 {
		log.Fatal("Error Code C: ", i)
	}

	i = MCIWorker("close capture", "", 0, 0)
	if i != 0 {
		log.Fatal("Error Code D: ", i)
	}

	fmt.Println("Audio saved to mic.wav")
}