Added example of a Redis SCAN command

Author: Jeremiah Lee Cohick

examples/scan.js

@@ -0,0 +1,34 @@
+var redis  = require("redis"),
+    client = redis.createClient();
+
+var cursor = 0;
+
+function scan() {
+    client.scan(
+        cursor,
+        "MATCH", "q:job:*",
+        "COUNT", "10",
+        function(err, res) {
+            if (err) throw err;
+
+            // Update the cursor position for the next scan
+            cursor = res[0];
+
+            // From <http://redis.io/commands/scan>:
+            // An iteration starts when the cursor is set to 0,
+            // and terminates when the cursor returned by the server is 0.
+            if (cursor === 0) {
+                return console.log('Iteration complete');
+            } else {
+                // Remember, more keys than COUNT or no keys may be returned
+                // See http://redis.io/commands/scan#the-count-option
+                if (res[1].length > 0) {
+                    return console.log('Array of matching keys', res[1]);
+                } else {
+                    // No keys were returned in this scan, but more keys exist.
+                    return scan();
+                }
+            }
+        }
+    );
+}