On 1-1-2014 14:43, Ray Holme wrote:

> I have noted that "cstring" must be shorter than 32k (divide by the
> character set width). This makes sense as the DB cannot import or show
> these longer strings.
>
> However, I am confused still. I would think that a "cstring" is going to
> always be a c-string (ascii string of characters terminated by null).
>
> If this is so, the db engine must convert internal strings to cstring
> for the udf and back again if the udf emits them.
>
> If not, two important things need to be well defined:
> a) there must be a call in the DB library to tell us what set we have
> so the UDF can handle multiple types
> OR
> you must write character set dependent routines
>
> AND
>
> b) there must be some documentation somewhere as to what these
> strings look like - I see stuff on the net, but it is rather hard to get
> a clear understanding
>
> I am thinking of UTF8 (net looks like this is 16bits per character, but
> I have heard 24 too).
>
> If a true cstring is still ascii with null terminator, this makes the
> UDF writer's job much easier (but it means some UDF functions cannot
> work for a lot of languages).
>
> Can anyone give me a clear answer on this and/or point me to a clear
> page describing UTF8 if I need to deal with it in a UDF.
>
> Happy New Year and thanks for any help you can provide.

Hi Ray,

Did you intend to send this mail to the Firebird-devel mailinglist, and
not the Firebird-Java group?

Happy New Year :)

Mark

--
Mark Rotteveel