Golang realpath with CGO (Linux)

rpath.go

package main

/*
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
*/
import "C"
import (
	"fmt"
	"unsafe"
)

func currentDir() []byte {
	return []byte{0x2e, 0x2f}
}

func rpath() string {
	relativePath := currentDir()
	limit := make([]byte, C.PATH_MAX)
	slink := make([]byte, len(relativePath)+1)
	copy(slink, relativePath)
	C.realpath(
		(*C.char)(unsafe.Pointer(&slink[0])),
		(*C.char)(unsafe.Pointer(&limit[0])))
	return C.GoString((*C.char)(unsafe.Pointer(&limit[0])))
}

func main() {
	fmt.Println(rpath())
}