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Subject: Re: [SG16-Unicode] Draft SG16 direction paper
From: Tom Honermann (tom_at_[hidden])
Date: 2018-10-07 21:21:27


On 10/07/2018 06:32 PM, Victor Zverovich wrote:
> > Existing programs depend on the ability to dynamically change the
> execution encoding (within reason) in order for a server process to
> concurrently serve multiple clients with different locale settings.
>
> This seems like a very weird use case because it effectively limits
> server to processing requests on one thread, since as mentioned
> elsewhere in the document per-thread locale setting is still in the
> proposal phase. Do you have any examples? In my experience changing
> locale dynamically more often than not breaks programs' expectations.

I don't have specific examples to share.  Code that does this pretty
much has to rely on extensions like POSIX uselocale() and Microsoft's
_configthreadlocale() since, as you note, taking a lock to ensure global
locale settings stay consistent effectively single threads requests.  A
quick code search of github for these functions has lots of hits, but
many are duplicate hits (if there is a way to get github to better
suppress similar hits, I'd be curious to know how to do that).

I agree that dynamically changing locale is rarely a good thing to do. 
It can be ok as part of program startup, but afterwards is asking for
trouble - same as changing other global state like current working
directory.  I just mentioned it because, despite likely being a bad
idea, there is existing code that does it.

Tom.

>
> On Tue, Oct 2, 2018 at 10:21 PM Tom Honermann <tom_at_[hidden]
> <mailto:tom_at_[hidden]>> wrote:
>
> Enclosed is a draft of an SG16 direction paper to be discussed at our
> meeting tomorrow.  It's rough, but I think in sufficient shape for
> discussion.
>
> If we manage to get through that paper, we'll discuss the paper Steve
> just posted to our mailing list [1] and/or Markus' feedback paper [2].
>
> Tom.
>
> [1]:
> http://www.open-std.org/pipermail/unicode/2018-October/000144.html
> [2]:
> https://docs.google.com/document/d/1aI0mBcH-d3BLjs8NRHgGECbA320LGFgo-SrNJ6VnLKE/edit
>
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> Unicode_at_[hidden] <mailto:Unicode_at_[hidden]>
> http://www.open-std.org/mailman/listinfo/unicode
>



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