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Date: Wed, 26 Sep 2012 02:12:09 +1000
Subject: Re: python file API
From: Chris Angelico <rosuav@gmail.com>
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Xref: csiph.com comp.lang.python:30106

On Wed, Sep 26, 2012 at 2:07 AM, Dennis Lee Bieber
<wlfraed@ix.netcom.com> wrote:
>         f.pos += delta
>
> would be a "seek.set" and with a naive driver might trigger a rewind to
> the start of the tape followed by a seek to the absolute position,
> whereas the seek from current location would only move the tape by the
> specified amount...

But a smart driver should always optimize the absolute seek to a
relative seek, unless there's a hard difference between them. After
all, the standard "read-ahead" technique is going to do an absolute
seek:

opaque_value = f.tell()
f.read(blah blah blah)
f.seek(opaque_value)

ChrisA