byte[] buf={'h', 'e', 'l', 'l', 'o', ' ', 'w', 'o', 'r', 'l', 'd'};
ByteArrayDataInputStream in=new ByteArrayDataInputStream(buf);
assert in.position() == 0;
int skipped=in.skipBytes(6);
assert skipped == 6;
assert in.position() == 6;
skipped=in.skipBytes(0);
assert skipped == 0;
assert in.position() == 6;