cvs commit: src/lib/libc/stdio vfscanf.c

[Peter Jeremy]

On Sat, Jul 05, 2003 at 10:13:02PM -0700, David Schultz wrote:
>On Thu, Jul 03, 2003, Peter Jeremy wrote:
>> It would seem cleaner to use a common underlying set of conversion
>> functions, similar to strtoX() but taking taking a FILE* and a width
>> instead of a char*.  The strtoX() functions can hand-craft the FILE
>> structure much as sscanf() does.
>
>In principle, you're right, but there are a number of problems.
>BDE touched on the key technical issues.  Another reason not to do
>as you suggest is that in order to seamlessly integrate the two,
>someone would have to overhaul the vendor's implementations of
>strtod() and strtodg().

Agreed.  There's probably some ongoing additional effort in maintaining
the three pieces of code but, based on BDE's comments, I'll withdraw
my suggestion.

>> This conversion also results in the 512
>> character limit on numeric strings.
>
>This is an age-old limitation.  I considered removing it, but then
>realized that I have yet to encounter anyone who cares.  512
>characters is a BIG floating point number---much larger than the
>precision supported by readily available hardware.

I doubt it's a real problem for anyone and it's not something that I
think is worth spending effort on (other than as part of a 'avoid
arbitrary limits' cleanup).  The limit would just disappear as a
side-effect: fstrtod() wouldn't need the incoming string copied into
a local buffer as strtod() does.

Peter