Date: Mon, 22 Dec 2025 10:55:16 +0100
From: "Peter J. Holzer" <hjp-pgsql@hjp.at>
To: pgsql-general@lists.postgresql.org
Subject: Re: PQexecPrepared() question
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Subject: Re: PQexecPrepared() question
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On 2025-12-21 17:30:38 -0800, Igor Korot wrote:
> On Sun, Dec 21, 2025 at 1:19=E2=80=AFPM Peter J. Holzer <hjp-pgsql@hjp.at=
> wrote:
> > As I see it, Igor has two options:
> >
> > 1) Send UTF8. wcstombs is the wrong tool for this, since it uses the
> >    current locale which is obviously not using UTF-8. I don't program in
> >    C++, but I'm pretty sure there is a portable way to encode a string
> >    in UTF-8.
[...]
> > I think 1) is the better strategy, but them I've been a UTF-8 fan-boy
> > for over 30 years ;-).
>=20
> Maybe all I need is something like this:
>=20
> convert(char *dest, const std::wstring src)
> {
>     const wchar_t *temp =3D src.c_str();
>     while( *dest )
>     {
>         dest++;
>     }
>     while( *temp )
>     {
>         *dest =3D *temp;
>         dest++;
>         temp++;
>     }
>     *dest++ =3D '\0';
>     *dest =3D '\0';
> }
>=20
> ?

I hope your compiler complains loudly about that code. You can't just
assign a wchar_t to a char and expect it to do anything sensible.

A short search points to std::wstring_convert, but that has been
deprecated in C++17, and it's not obvious to me what the replacement is.

There is always ICU, of course, but that feels like cracking a nut with
a sledgehammer.=20

Personally, I might roll my own if an hour of googling doesn't turn up
anything promising (UTF-8 encoding is quite simple), but that shouldn't
be necessary.


        hjp

--=20
   _  | Peter J. Holzer    | Story must make more sense than reality.
|_|_) |                    |
| |   | hjp@hjp.at         |    -- Charles Stross, "Creative writing
__/   | http://www.hjp.at/ |       challenge!"

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