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Date: Thu, 9 Jul 2026 09:04:54 +0200
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Subject: Re: [PATCH] ecpg: use memcpy in a few length-based copies
To: Haibo Yan <tristan.yim@gmail.com>,
 PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
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From: Peter Eisentraut <peter@eisentraut.org>
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On 08.07.26 21:24, Haibo Yan wrote:
> I noticed a few places in ecpg that use strncpy() even though the code already
> knows how many bytes to copy.
> 
> For example, some paths copy N bytes into a temporary buffer and then add the
> terminating NUL explicitly.  There is also one small substring copy in
> pgtypeslib/datetime.c.  memcpy() seems a better fit for those cases.

Why is it better?  At least strncpy() enforces that the target is a char 
array, which memcpy() doesn't.

At a quick glance, strlcpy() might be more suitable in some of the cases 
you found.