Classification of character set conversion functions

[Florian Weimer]

On 10/04/2016 10:48 AM, Igor Liferenko wrote:
> Hi all,
>
> In GNU libc reference
>     https://www.gnu.org/software/libc/manual/html_node/Charset-Function-Overview.html
> it is said:
>
>     A Unix C library contains three different
>     sets of functions in two families to
>     handle character set conversion.
>
> Unfortunately, it is not specified in the GNU libc reference which
> exactly are these families and sets.

I wouldn't read too much into it.  It's just an attempt to present the 
material in a somewhat structured fashion.  It doesn't really say 
something about the functions themselves.

> My questions are:
>
>   I) is the following classification correct?
>   II) to which family and set each of the following functions belongs?
>   III) is the following list of functions complete?
>
> --- Classification ---
>
> Families:
>   1) character sets that are directly specified by the functions
>   2) character sets that are not directly specified by the functions

I think the manual tries to distinguish between functions from C90 and 
functios from other sources.

> Sets of functions:
>
>   a) Restartable Conversion Functions.
>   b) Non-reentrant Conversion Functions.
>   c) Generic Charset Conversion Functions.

I haven't checked, but the C90 functions are probably all among the 
non-reentrant functions (which one should not use).

Florian