Re: A micro-optimisation for walkdir()

Thomas Munro <thomas(dot)munro(at)gmail(dot)com> writes:
> On Thu, Sep 3, 2020 at 5:36 PM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> Both of these concerns would abate if we had get_dirent_type()
>> just throw an error itself when stat() fails, thereby removing the
>> PGFILETYPE_ERROR result code. I'm not 100% sold either way on
>> that, but it's something to think about. Is there ever going
>> to be a reason for the caller to ignore an error?

> Hmm. Well I had it like that in an earlier version, but then I
> couldn't figure out the right way to write code that would work in
> both frontend and backend code, without writing two copies in two
> translation units, or putting the whole thing in a header. What
> approach do you prefer?

Well, there are plenty of places in src/port/ where we do things like

#ifndef FRONTEND
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not get junction for \"%s\": %s",
path, msg)));
#else
fprintf(stderr, _("could not get junction for \"%s\": %s\n"),
path, msg);
#endif

I don't see a compelling reason why this function couldn't report
stat() failures similarly, especially if we're just going to have
the callers do exactly the same thing as that anyway.

regards, tom lane