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Truncate beginning of a file

file.truncate(X ) will truncate the file to at most X bytes (i.e. leave
the first X bytes of the file and throw away the rest). Is there a way
to throw away, say, the first X bytes of the file, and leave the rest?
(Without opening the same file for reading, reading and processing,
overwriting the file with the new processed data, etc.)
Jun 27 '08 #1
2 3372
On Sun, 04 May 2008 22:06:42 -0700, s0suk3 wrote:
file.truncate(X ) will truncate the file to at most X bytes (i.e. leave
the first X bytes of the file and throw away the rest). Is there a way
to throw away, say, the first X bytes of the file, and leave the rest?
(Without opening the same file for reading, reading and processing,
overwriting the file with the new processed data, etc.)
No.

Ciao,
Marc 'BlackJack' Rintsch
Jun 27 '08 #2
s0****@gmail.co m writes:
file.truncate(X ) will truncate the file to at most X bytes (i.e.
leave the first X bytes of the file and throw away the rest).
Yes, by (IIRC) asking the filesystem to do this in a simple operation.
Most (all?) filesystems support this operation either directly or with
little effort.
Is there a way to throw away, say, the first X bytes of the file,
and leave the rest? (Without opening the same file for reading,
reading and processing, overwriting the file with the new processed
data, etc.)
I don't know of any filesystem that supports this operation without
reading the file data. The built-in 'file' type doesn't support it.

--
\ "It's easy to play any musical instrument: all you have to do |
`\ is touch the right key at the right time and the instrument |
_o__) will play itself." -- Johann Sebastian Bach |
Ben Finney
Jun 27 '08 #3

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