On Tue, 24 Jun 2003 20:16, you wrote:
> On Tue, 2003-06-24 at 20:06, Rob Stockley wrote:
> > If it's a text file then how about,
> >
> > cat your_file | tail --bytes=N > your_file
> >
> > where N is the number of bytes to be kept. Can piping be made to operate
> > serially using a temporary file? Perhaps this is a little dangerous to
> > be writing back to the same file. Maybe a short script? Rambling
> > again.... :>
>
> Nope needed to be
>
> cat your_file | tail --bytes=N > /tmp/tempfile ; mv /tmp/tempfile
> your_file
>
> Probably still not quite right.
Tim's one is the closest

[EMAIL PROTECTED] chris $ gcc -o truncate truncate.c
[EMAIL PROTECTED] chris $ dd if=/dev/zero of=testfile bs=1024 count=1024
1024+0 records in
1024+0 records out
[EMAIL PROTECTED] chris $ ls -l testfile
-rw-r--r--    1 chris    users     1048576 Jun 24 20:16 testfile
[EMAIL PROTECTED] chris $ ./truncate testfile 500000
[EMAIL PROTECTED] chris $ ls -l testfile
-rw-r--r--    1 chris    users      500000 Jun 24 20:17 testfile
[EMAIL PROTECTED] chris $ ./truncate testfile 500001
[EMAIL PROTECTED] chris $ ls -l testfile
-rw-r--r--    1 chris    users      500001 Jun 24 20:17 testfile
[EMAIL PROTECTED] chris $ echo $?
0

True truncation? Shows the way to go though.
Sorry to be a perfectionist.

--
C. S.

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