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Message-ID: <000e01c3be0e$b8774670$1200a8c0@gsicomp.on.ca>
From: "Matt Emmerton" <matt@gsicomp.on.ca>
To: "Dan Nelson" <dnelson@allantgroup.com>,
	"Kevin D. Kinsey, DaleCo, S.P." <kdk@daleco.biz>
References:
	<20031209015125.74977.qmail@web14806.mail.yahoo.com><200312090259.23677@harrymail>
	<3FD54A37.8050503@daleco.biz> <20031209043046.GC2435@dan.emsphone.com>
Date: Mon, 8 Dec 2003 23:41:32 -0500
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cc: homeyra g <homeyra_s@yahoo.com>
cc: freebsd-questions@freebsd.org
cc: Harald Schmalzbauer <h@schmalzbauer.de>
Subject: Re: a technical how to
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> In the last episode (Dec 08), Kevin D. Kinsey, DaleCo, S.P. said:
> > Harald Schmalzbauer wrote:
> > >On Tuesday 09 December 2003 02:51, homeyra g wrote:
> > >>So, I hope this is the right address for this type of question. If
> > >>not would you please forward this and/or let me know the correct
> > >>address.
> > >>
> > >>Thanks,
> > >>
> > >>Here is the question: How to truncate a file from the begining to a
> > >>certain point in the file?
>
> If you're writing a script, use the /usr/bin/truncate command.  If
> you're writing a C program, use the truncate() function.

truncate() essentially alters the "end-of-file" position, by decreasing it
(truncating the file) or increasing it (extending the file.)

I think what the requestor wants is a way to adjust the "start-of-file"
position, which would effectively "truncate [sic] a file from the beginning
to a certain point in the file".

One way to accomplish this is as follows:

split -b 1024 /path/to/data
rm <files that represent data to "truncate">
cat * > data.new

--
Matt Emmerton