QUESTION TO PORTERS:
Would providing <monetary.h>, strfmon(3), and strfmon_l(3)
in our libc make porters' lives easier, or are these interfaces
used so rarely in real-world programs that it does not matter?
Hi John,
John Zaitseff wrote on Wed, Aug 17, 2022 at 12:29:20PM +1000:
> Apologies in advance if I am sending this to the wrong list...
Since strfmon(3) is a useless API and this discussion is exclusively
about compatibility, asking on ports@ would have been better,
more accurately targetting the intended audience, but bugs@ is not
outright wrong either because OpenBSD aims to support POSIX unless
there are specific reasons to not support something, and <monetary.h>,
strfmon(3), and strfmon_l(3) are specified by POSIX.
However, strfmon(3) is even more ill-designed than other POSIX
locale-related functions:
- strfmon(3) is designed to interpret the same floating-point
number differently depending on the user's locale(1).
But whether a user owns 42.00 Turkish Lira or 42.00 Pound Sterling
is *not* a matter of personally preferred output conventions.
Consequently, i can hardly imagine any situation where using
strfmon*(3) might make any sense. Using this functions will
usually misrepresent the currency owned by the user, causing
wrong output.
- Arguably, you can use the "!" flag to suppress the misfeature
of having the currency symbol depend on the user's locale,
but then, strfmon(3) mostly duplicates functionality already
provided by printf(3) with a very small number of gratuitious
variations, so i see no conceivable motivation for using the
interface with "!" either.
For those reasons, i think using <monetary.h> is a terrible idea in the
first place and we should not add it to our libc if we can avoid it.
That said, even if an API is abominable (like this one),
support can sometimes be considered *if* it is used by enough
ports(7) that its absense causes pain for OpenBSD porters.
The only condition in such cases is that a dummy version can be
provided that poses no security risks. I do not doubt that
would be possible for strfmon(3) and strfmon_l(3).
> A few years ago, Frederic Cambus packaged Star Traders, my simple
> game of interstellar trading, for OpenBSD ("trader"). In doing so,
> he bundled FreeBSD's version of strfmon() as that function is
> required by my program.
My personal recommendation would be to stop using the bad function
in your program.
> Longer term, however, could OpenBSD include <monetary.h>, strfmon()
> and strfmon_l(), possibly by copying these from the latest version
> of FreeBSD.
Well, as usual, the FreeBSD version of locale functions is seriously
bloated, so if porters tell me that lack of the function causes
pain for them, i would radically strip it down before commit.
Yours,
Ingo
