From 680964fca5d82384243a6f04a99accb95d20d2fd Mon Sep 17 00:00:00 2001
From: Niko Fink <nfink95@gmail.com>
Date: Wed, 12 Oct 2016 10:34:56 -0400
Subject: [PATCH] don't fail silently

Redirect subprocess stderr to parent's stderr and print error events when the child process could not be spawned or killed.
---
 main.js | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/main.js b/main.js
index 9293c99..ea39a72 100644
--- a/main.js
+++ b/main.js
@@ -12,7 +12,7 @@ var mainProcessShutdown = false;
 
 var initChildProcess = function()
 {
-	child = spawn("node", [__dirname + "/" + "rc522_output.js"]);
+	child = spawn("node", [__dirname + "/" + "rc522_output.js"], { stdio: ['pipe', 'pipe', process.stderr] });
 	var linereader = readline.createInterface(child.stdout, child.stdin);
 
 	linereader.on('line', function (rfidTagSerialNumber) {
@@ -28,6 +28,10 @@ var initChildProcess = function()
 			initChildProcess();
 		}
 	});
+
+	child.on('error', function(err) {
+		console.log("Error with RC522 subprocess", err);
+	});
 };
 
 // SIGTERM AND SIGINT will trigger the exit event.