truncating a file from the top down

[Mike Rovner]

Right. Thanks for the correction.

Fredrik Lundh wrote:
> Mike Rovner wrote:
> 
> 
>>if os.stat says the_file is too big:
>>  fh = open(the_file, 'rb')
>>  fh.seek(2008, 2)
> 
> 
> should be
> 
>     fh.seek(-2008, 2)
> 
> right?
> 
> 
>>  data = fh.read()
>>  fh.close()
>>  assert len(data)==2008 # you may want some error processing here
>>  fh = open(the_file, 'wb')
>>  fh.write(data)
>>  fh.close()
> 
> 
> or
> 
>     if os.path.getsize(the_file) > TOO_BIG:
>         fh = open(the_file, 'rb+')
>         fh.seek(-2008, 2)
>         data = fh.read()
>         fh.seek(0) # rewind
>         fh.write(data)
>         fh.truncate()
>         fh.close()
> 
> </F> 
> 
> 
>