golang中.a文件是什么

package mainimport "C"import (

    //"fmt"

    "github.com/tuotoo/qrcode"

    "os")//export GetQrcodeStringfunc GetQrcodeString(cstring *C.char) *C.char {

    //func GetQrcodeString() *C.char {

    path := C.GoString(cstring)

    //path := "qrcode.png"

    fi, err := os.Open(path)

    if err != nil {

        //fmt.Println(err.Error())

        return C.CString(path)

    }

    defer fi.Close()

    qrmatrix, err := qrcode.Decode(fi)

    if err != nil {

        //fmt.Println(err.Error())

        return C.CString(path)

    }

    //fmt.Println(qrmatrix.Content)

    //return C.Cstring(qrmatrix.Content)

    gostr := qrmatrix.Content

    cstr := C.CString(gostr)

    return cstr}func main() {}

go build -buildmode=c-archive -o pkgqrcode.a pkgqrcode.go