Classification of character set conversion functions

[Igor Liferenko]

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.

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

Sets of functions:

  a) Restartable Conversion Functions.
  b) Non-reentrant Conversion Functions.
  c) Generic Charset Conversion Functions.

--- List of character set conversion functions ---

iconv()

mblen()
mbtowc()
mbstowcs()
wctob()

btowc()
fgetwc()
fgetws()
fputwc()
fputws()
fwide()
fwprintf()
fwscanf()
getwc()
getwchar()
iswalnum()
iswalpha()
iswcntrl()
iswctype()
iswdigit()
iswgraph()
iswlower()
iswprint()
iswpunct()
iswspace()
iswupper()
iswxdigit()
putwc()
putwchar()
swprintf()
swscanf()
towctrans()
towlower()
towupper()
ungetwc()
vfwprintf()
vfwscanf()
vswprintf()
vswscanf()
vwprintf()
vwscanf()
wcrtomb()
wcscat()
wcschr()
wcscmp()
wcscoll()
wcscpy()
wcscspn()
wcsftime()
wcslen()
wcsncat()
wcsncmp()
wcsncpy()
wcspbrk()
wcsrtombs()
wcsrchr()
wcsspn()
wcsstr()
wcstod(), wcstof(), wcstold()
wcstoimax(), wcstoumax()
wcstok()
wcstol(), wcstoll()
wcstombs()
wcstoul(), wcstoull()
wcsxfrm()
wctob()
wctomb()
wctrans()
wctype()
wmemchr()
wmemcmp()
wmemcpy()
wmemmove()
wmemset()
wprintf()
wscanf()

Regards,
Igor