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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Thomas Munro <thomas.munro@gmail.com>
cc: Tristan Partin <tristan@neon.tech>,
        pgsql-hackers <pgsql-hackers@postgresql.org>
Subject: Re: On non-Windows, hard depend on uselocale(3)
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Comments: In-reply-to Thomas Munro <thomas.munro@gmail.com>
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Thomas Munro <thomas.munro@gmail.com> writes:
> If we are sure that we'll *never* want locale-aware printf-family
> functions (ie we *always* want "C" locale), then in the thought
> experiment above where I suggested we supply replacement _l()
> functions, we could just skip that for the printf family, but make
> that above comment actually true.  Perhaps with Ryu, but otherwise by
> punting to libc _l() or uselocale() save/restore.

It is pretty annoying that we've got that shiny Ryu code and can't
use it here.  From memory, we did look into that and concluded that
Ryu wasn't amenable to providing "exactly this many digits" as is
required by most variants of printf's conversion specs.  But maybe
somebody should go try harder.  (Worst case, you could do rounding
off by hand on the produced digit string, but that's ugly...)

			regards, tom lane