diff --git a/build/npm/update-grammar.js b/build/npm/update-grammar.js
index d9396469e70..a344dcf2f53 100644
--- a/build/npm/update-grammar.js
+++ b/build/npm/update-grammar.js
@@ -67,7 +67,9 @@ exports.update = function (repoId, repoPath, dest, modifyGrammar) {
 	}, console.error);
 }
 if (path.basename(process.argv[1]) === 'update-grammar.js') {
-	exports.update(process.argv[2], process.argv[3], process.argv[4]);
+	for (var i = 3; i < process.argv.length; i+=2) {
+		exports.update(process.argv[2], process.argv[i], process.argv[i+1]);
+	}
 }
 
 
diff --git a/extensions/cpp/package.json b/extensions/cpp/package.json
index c3bf4571e02..d83ade94392 100644
--- a/extensions/cpp/package.json
+++ b/extensions/cpp/package.json
@@ -3,6 +3,9 @@
 	"version": "0.1.0",
 	"publisher": "vscode",
 	"engines": { "vscode": "*" },
+	"scripts": {
+		"update-grammar": "node ../../build/npm/update-grammar.js atom/language-c grammars/c.cson ./syntaxes/c.json grammars/c%2B%2B.cson ./syntaxes/c++.json"
+	},
 	"contributes": {
 		"languages": [{
 			"id": "c",