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Re: One example of code I can't understand
From: |
Stephen J. Turnbull |
Subject: |
Re: One example of code I can't understand |
Date: |
Wed, 22 Jul 2009 15:58:28 +0900 |
Kenichi Handa writes:
> It is theoretically possible to modify all of them to use a
> multibyte buffer that contains only ASCII and eight-bit
> chars. But, as it may make the operations slow, I don't see
> a merit in doing that.
XEmacs has always done it this way; it is more than a theoretical
possibility. In XEmacs it doesn't make much difference for the
operations you describe (less than a factor of 2) because the overhead
of interfacing to the pipes is greater than the overhead of
conversion. This is based on some profiling Ben did many years ago;
ISTR it was basically linear up to 128MB or maybe 256MB. I don't
recall the exact numbers, but I do remember being very surprised that
it was substantially less than 2.
In XEmacs, I think it makes a much bigger difference for mail buffers
(VM, or Gnus nnfolder) because of the frequency of byte<->char
conversions in those more or less random access applications.
One example of code I can't understand, Richard Stallman, 2009/07/19
Re: One example of code I can't understand, Richard Stallman, 2009/07/21
Re: One example of code I can't understand, Eli Zaretskii, 2009/07/21