Re: c++ strings and UTF-8 (other charsets)

[Marcel Ruff <mr@xxxxxxxxxxxxxxx>]

Rich Felker wrote:
> On Sat, Feb 24, 2007 at 06:13:37PM +0100, Julien Claassen wrote:
>   
> > Hi!
> >   What I meant about UTF-8-strings in c++: I mean in c and c++ they're not 
> > standard like in Java.
> >     
>
> UTF-16, used by Java, is also variable-width. It can be either 2 bytes
> or 4 bytes per character. Support for the characters that use 4 bytes
> is generally very poor due to the misconception that it's
> fixed-width.. :(
>
>   
> > I think UTF-8 is a variable width multibyte charset, so 
> > there are specific problems in handling them allocating the right space. I 
> > mean the Glib contains something like UString and QT has its QStrings, which 
> > I think are also UTF-8 capable.
> >     
As far as i know:

Using UTF-8 in C or C++ is very simple:
As UTF-8 may not contain '\0' you can simply use all
functions as before (strcmp(), std::string etc.).
Old code doesn't need to be ported.

The only place to take care is when interfacing other libraries
using wchar_t and such (UTF-16, UTF-32), here
you need to convert using functions like wcstrtombs(), mbstrtowcs(), 
mbrtowc() and such.
This works well on Linux, Windows or other OS,

Marcel
> All strings are UTF-8 capable; the unit of data is simply bytes
> instead of characters. If you're looking for a class that treats
> strings as a sequence of abstract characters rather than a sequence of
> bytes, you could look for a library to do this or write your own.
> However I suspect the most useful way to do this on C++ would be to
> extend whatever standard byte-based string class you're using with a
> derived class.
>
> Maybe there's something like this built in to the C++ STL classes
> already that I'm not aware of. As I said I don't know much of (modern)
> C++. Can someone who knows the language better provide an answer?
>
> It would also be easier to provide you answers if we knew better what
> you're trying to do with the strings, i.e. whether you just need to
> store them and spit them back in output, or whether you need to do
> higher-level unicode processing like line breaks, collation,
> rendering, etc.
>
> Rich
>
> --
> Linux-UTF8:   i18n of Linux on all levels
> Archive:      http://mail.nl.linux.org/linux-utf8/
>
>
>   


--
Linux-UTF8:   i18n of Linux on all levels
Archive:      http://mail.nl.linux.org/linux-utf8/