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Michael S wrote:Only if you iterate in order of increasing memory address, which is not the only possibility.On Tue, 3 Sep 2024 17:41:40 +0200Assume a buffer consisting of records of some type, some of them marked as deleted. Iterating over them while removing the gaps means that you are always copying to a destination lower in memory, right?
Terje Mathisen <terje.mathisen@tmsw.no> wrote:
>Michael S wrote:>3 years ago Terje Mathisen wrote that many years ago he read that>
behaviour of memcpy() with overlappped src/dst was defined.
https://groups.google.com/g/comp.arch/c/rSk8c7Urd_Y/m/ZWEG5V1KAQAJ
Mitch Alsup answered "That was true in 1983".
So, two people of different age living in different parts of the
world are telling the same story. May be, there exist old popular
book that said that it was defined?
It probably wasn't written in the official C standard, which I
couldn't have afforded to buy/read, but in a compiler runtime doc?
>
Specifying that it would always copy from beginning to end of the
source buffer, in increasing address order meant that it was
guaranteed safe when used to compact buffers.
>
What is "compact buffers" ?
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