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Re: tail

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From: ros...@gmail.com (Chris Angelico)
Newsgroups: comp.lang.python
Subject: Re: tail
Date: Sun, 24 Apr 2022 10:39:48 +1000
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by: Chris Angelico - Sun, 24 Apr 2022 00:39 UTC

On Sun, 24 Apr 2022 at 10:04, Cameron Simpson <cs@cskk.id.au> wrote:
>
> On 24Apr2022 08:21, Chris Angelico <rosuav@gmail.com> wrote:
> >On Sun, 24 Apr 2022 at 08:18, Cameron Simpson <cs@cskk.id.au> wrote:
> >> An approach I think you both may have missed: mmap the file and use
> >> mmap.rfind(b'\n') to locate line delimiters.
> >> https://docs.python.org/3/library/mmap.html#mmap.mmap.rfind
> >
> >Yeah, I made a vague allusion to use of mmap, but didn't elaborate
> >because I actually have zero idea of how efficient this would be.
> >Would it be functionally equivalent to the chunking, but with the
> >chunk size defined by the system as whatever's most optimal? It would
> >need to be tested.
>
> True. I'd expect better than single byte seek/read though.
>

Yeah, I think pretty much *anything* would be better than single byte seeks.

ChrisA

grep me no patterns and I'll tell you no lines.

devel / comp.lang.python / Re: tail