SD Timestamp read?

I would compare last change time of 2 files in SD.
I use <SD.h>'s file.timestamp(*) to set it, but i don’t know how read it!

I hope someone can help me, thanks.

Here is a sketch for the SdFat library that opens each file in the root directory and prints

file_name year-month-day hour:minute:second

for the last write date and time.

/*
 * Open all files in the root dir and print their filename
 */
#include <SdFat.h>

// SD chip select pin
const uint8_t chipSelect = SS;

// file system object
SdFat sd;

SdFile file;

// define a serial output stream
ArduinoOutStream cout(Serial);
//------------------------------------------------------------------------------
void setup() {
  dir_t dir;
  char name[13];

  Serial.begin(9600);

  // initialize the SD card at SPI_HALF_SPEED to avoid bus errors with
  // breadboards.  use SPI_FULL_SPEED for better performance.
  if (!sd.begin(chipSelect, SPI_HALF_SPEED)) sd.initErrorHalt();

  // open next file in root.  The volume working directory, vwd, is root
  while (file.openNext(sd.vwd(), O_READ)) {
    file.getFilename(name);
    file.dirEntry(&dir);
    cout << name << ' ';
    cout << FAT_YEAR(dir.lastWriteDate) << '-' << setfill('0');
    cout << setw(2) << (int)FAT_MONTH(dir.lastWriteDate) << '-';
    cout << setw(2) << (int)FAT_DAY(dir.lastWriteDate) << ' ';
    cout << setw(2) << (int)FAT_HOUR(dir.lastWriteTime) << ':';
    cout << setw(2) << (int)FAT_MINUTE(dir.lastWriteTime) << ':';
    cout << setw(2) << (int)FAT_SECOND(dir.lastWriteTime) << endl;
    file.close();
  }
  cout << "Done" << endl;
}
//------------------------------------------------------------------------------
void loop() {
}

Here is example output:

LOGFILE.BIN 2000-01-01 01:00:00
DATE.TXT 2012-07-14 10:39:32
Done

The time-stamp has not been set on the first file.