Reading the first MB of a binary file

[Marc 'BlackJack' Rintsch]

On Sun, 25 Jan 2009 08:37:07 -0800, Max Leason wrote:

> I'm attempting to read the first MB of a binary file and then do a md5
> hash on it so that i can find the file later despite it being moved or
> any file name changes that may have been made to it. These files are
> large (350-1400MB) video files and i often located on a different
> computer and I figure that there is a low risk for generating the same
> hash between two files. The problem occurs in the read command which
> returns all \x00s. Any ideas why this is happening?
> 
> Code:
>>>>>open("Chuck.S01E01.HDTV.XViD-YesTV.avi", "rb").read(1024)
> b'\x00\x00\x00\x00\x00\x00....\x00'

As MRAB says, maybe the first 1024 actually *are* all zero bytes.  Wild 
guess:  That's a file created by a bittorrent client which preallocates 
the files and that file above isn't downloaded completely yet!?

Ciao,
	Marc 'BlackJack' Rintsch