package reuseport import ( "net" "os" ) const ( EADDRINUSE = "address in use" ECONNREFUSED = "connection refused" ) // reuseErrShouldRetry diagnoses whether to retry after a reuse error. // if we failed to bind, we should retry. if bind worked and this is a // real dial error (remote end didnt answer) then we should not retry. func reuseErrShouldRetry(err error) bool { if err == nil { return false // hey, it worked! no need to retry. } // if it's a network timeout error, it's a legitimate failure. if nerr, ok := err.(net.Error); ok && nerr.Timeout() { return false } e, ok := err.(*net.OpError) if !ok { return true } e1, ok := e.Err.(*os.PathError) if !ok { return true } switch e1.Err.Error() { case EADDRINUSE: return true case ECONNREFUSED: return false default: return true // optimistically default to retry. } }