added arduino, modified build

arduino/libraries/SD/examples/listfiles/listfiles.ino

@@ -0,0 +1,80 @@
+/*
+  Listfiles
+
+ This example shows how print out the files in a
+ directory on a SD card
+
+ The circuit:
+ * SD card attached to SPI bus as follows:
+ ** MOSI - pin 11
+ ** MISO - pin 12
+ ** CLK - pin 13
+ ** CS - pin 4 (for MKRZero SD: SDCARD_SS_PIN)
+
+ created   Nov 2010
+ by David A. Mellis
+ modified 9 Apr 2012
+ by Tom Igoe
+ modified 2 Feb 2014
+ by Scott Fitzgerald
+
+ This example code is in the public domain.
+
+ */
+#include <SPI.h>
+#include <SD.h>
+
+File root;
+
+void setup() {
+  // Open serial communications and wait for port to open:
+  Serial.begin(9600);
+  while (!Serial) {
+    ; // wait for serial port to connect. Needed for native USB port only
+  }
+
+  Serial.print("Initializing SD card...");
+
+  if (!SD.begin(4)) {
+    Serial.println("initialization failed!");
+    while (1);
+  }
+  Serial.println("initialization done.");
+
+  root = SD.open("/");
+
+  printDirectory(root, 0);
+
+  Serial.println("done!");
+}
+
+void loop() {
+  // nothing happens after setup finishes.
+}
+
+void printDirectory(File dir, int numTabs) {
+  while (true) {
+
+    File entry =  dir.openNextFile();
+    if (! entry) {
+      // no more files
+      break;
+    }
+    for (uint8_t i = 0; i < numTabs; i++) {
+      Serial.print('\t');
+    }
+    Serial.print(entry.name());
+    if (entry.isDirectory()) {
+      Serial.println("/");
+      printDirectory(entry, numTabs + 1);
+    } else {
+      // files have sizes, directories do not
+      Serial.print("\t\t");
+      Serial.println(entry.size(), DEC);
+    }
+    entry.close();
+  }
+}
+
+
+