C:\test>1031021-i.pl <1031021.dat
1367160156
1367160362

C:\test>dir 1031021*
28/04/2013  15:30               193 1031021-i.pl
28/04/2013  15:04     5,272,940,608 1031021.dat
28/04/2013  15:46           316,385 1031021.idx
28/04/2013  15:29               374 1031021.pl