Why does skip on new FileInputStream(FileDescriptor.in) not work?

Question

Java

Why does skip on new FileInputStream(FileDescriptor.in) not work? Although with System.in skip in similar code it works...

import java.io.FileDescriptor;
import java.io.FileInputStream;
import java.io.IOException;

public class Soltuion {

  public static void main(String[] args) throws IOException {
    FileInputStream keyboardStream = new FileInputStream(FileDescriptor.in);
    System.out.print(keyboardStream.read() + " ");
    keyboardStream.skip(100);  // любой аргумент напиши - не сработает 
    System.out.print(keyboardStream.read() + " ");
    System.out.print(keyboardStream.read() + " ");

    // Ввод: 8
    // Вывод: 56 13 10 (всё считал, а не только 56 c ожиданием нового ввода)
  }
}

Answer 1

Since the FileInputStream overrides the skip from the InputStream and calls the native skip. Wrap in BufferedInputStream