I gave a try with a simple file and it works fine.
You truncate to 0, means your file will be empty afterwards.
if size, 0 in your case, is greater than the files length then the behavior is undefined.
Means you got to have some content in your file. Do you have content in your file?
See: tuncate

Cheers!
Tobias

In reply to Re: problems with truncate function by tobias_hofer
in thread problems with truncate function by david2008

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