FYI we're very interested in decimal floating-point support. Let me
know if you need any help.

Irek

On 3/3/09, Roland Mainz <[email protected]> wrote:
> Glenn Fowler wrote:
>  > On Tue, 03 Mar 2009 16:40:43 +0100 Roland Mainz wrote:
>  > > Glenn Fowler wrote:
>  > > > the second field contains letters that correspond to the
>  > > > optional compile-time SHOPT_* features (when ksh was built)
>  > > >
>  > > >         A       SHOPT_AUDIT
>  > > >         B       SHOPT_BASH
>  >
>  > > Is it possible reserve "D" (and "typeset -D") for "IEEE 754-2008-style
>  > > decimal floating point", please (this differs from normal IEEE754
>  > > floating-point math that it uses bash10 instead of base2 and is needed
>  >                                    ^^^^^^
>  > (maybe you need a break from shell hacking?:)
>
>  No, I am serious in this case. IEEE 754-2008 supports two _different_
>  floating-point formats:
>  a) The "traditional" base2 floating-point format we all know from IEEE
>  754-1985 and ISO C99 and ISO C++ etc.
>  b) The "new" base10 (="decimal") floating-point format (which comes with
>  new headers, library functions (see decNumber below) and C datatypes)
>
>  These two are different entities, use different datatypes and can be
>  used in the same application (the difference are in binary
>  representation (decimal floating-point uses densely packed
>  floating-point), rounding and text<--->binary conversions and other
>  little details).
>
>  > > for stuff like financial applications (somewhere I've queued a longer
>  > > email abóut this in my drafts folder)) ?
>  >
>  > what are the coding/runtime mechanisms for IEEE 754-2008 decimal floating 
> point
>
>  1. See
>  http://en.wikipedia.org/wiki/Decimal_floating_point#IEEE_754-2008_encoding
>  2. Newer compilers like gcc >= 4.2 support "Decimal Floating Point"
>  directly (e.g. it is expected that in the future all newer compilers
>  will support decimal floating-point - the transition may need another
>  four or five years for all platforms (IBM is likely going to lead in
>  this area since their high-end Power hardware supports decimal floating
>  point in hardware already)).
>  3. IBM provides the ANSI-C "decNumber" library (see
>  http://www.alphaworks.ibm.com/tech/decnumber) under a MIT license for
>  compilers/platforms which do not support decimal-floating-point yet
>
>  > recall that ast does its own string<=>fp conversions
>  > these work for IEEE 754
>  > but no provisions have been made for IEEE 754-2008
>  > (it may be that no provisions are necessary)
>
>  No provisions are neccesary for the traditional IEEE 754-2008 base2
>  floating-point math ([a] above) ... but base10 math ([b] above) is
>  something completely new.
>
>  > in particular, can a single process switch between IEEE 754 and IEEE 
> 754-2008?
>
>  Yes, see above. Both [a] and [b] are seperate things.
>
>  ----
>
>  Bye,
>  Roland
>
>  --
>   __ .  . __
>   (o.\ \/ /.o) [email protected]
>   \__\/\/__/  MPEG specialist, C&&JAVA&&Sun&&Unix programmer
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>   (;O/ \/ \O;)
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