iostream changes locale to format a number

[Stephen M.Webb]

On May 3, 2002 08:30 am, Paolo Carlini wrote:
> Paolo Carlini wrote:
> > Are you willing to contribute a patch against the current mainline
> > libstdc++-v3 sources for public discussion (that setlocale ...
> > setlocale pattern is present in quite a few different places) ?
>
> Let me point out, however, that, assuming your analysis is correct (I
> believe is) the solution cannot be as simple as you seems to assume:
> the string returned by the first setlocale must be saved! 

That's not correct.  The first call with an empty string will set the 
global locale object to that of the operating environment (eg. the 
value of the LC_ALL environment variable in a POSIX environment).

The remaining calls, with a NULL locale value, are simply queries.

The problem described is that writing a numeric value to a standard 
IOStream will alter the global POSIX locale.  The fix would be for the 
IOStreams that set the POSIX locale to save and restore the existing 
values instead of treading all over user data.

I can't spot anywhere in the trunk code where this is done 
improperly.  I'll set up a test case and see if (a) it's still 
happening and (b) isolate the cause.

-- 
Stephen M. Webb