creating/modifying sparse files on linux

[draghuram at gmail.com]

Thanks for the info on xrange. Writing single char is just to get going
quickly. I knew that I would have to improve on that. I would like to
write chunks of 1MB which would require that I have 1MB string to
write. Is there any simple way of generating this 1MB string (other
than keep appending to a string until it reaches 1MB len)? I don't care
about the actual value of the string itself. 

Thanks,
Raghu.