From 857446f1f6c1e356b399af9a21f4bf5aaa8feb1f Mon Sep 17 00:00:00 2001
From: Daniel Lublin <daniel@lublin.se>
Date: Thu, 9 Feb 2023 08:22:51 +0100
Subject: [PATCH] Make Open return a nil interface on failure

Closes #154

Signed-off-by: Daniel Lublin <daniel@lublin.se>
---
 serial.go | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/serial.go b/serial.go
index 2bb7f3e..6b4869c 100644
--- a/serial.go
+++ b/serial.go
@@ -77,7 +77,13 @@ type ModemOutputBits struct {
 
 // Open opens the serial port using the specified modes
 func Open(portName string, mode *Mode) (Port, error) {
-	return nativeOpen(portName, mode)
+	port, err := nativeOpen(portName, mode)
+	if err != nil {
+		// Return a nil interface, for which var==nil is true (instead of
+		// a nil pointer to a struct that satisfies the interface).
+		return nil, err
+	}
+	return port, err
 }
 
 // GetPortsList retrieve the list of available serial ports