Chapter 6. LOCALE technology

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iconv_t conv = iconv_open(tocode, INTERNALCODE);

(conversion and writing...)

iconv_close(conv);

} else {

(original writing routine)

}

Note that whole reading should be done at once since otherwise you may divide multibyte charac 

ter. You can consult the

iconv_prog.c

file in the distribution of GNU libc for usage of

iconv()

.

Though

nl_langinfo()

is a standard function of XPG5 and GNU libc supports it, it is not

very portable. And more, there are no standard for encoding names for

nl_langinfo()

and

iconv_open()

. If this is a problem, you can use Bruno Haible's libiconv (

http://www.gnu.

org/software/libiconv/

). It has

iconv()

,

iconv_open()

, and

iconv_close()

. And

more, it has

locale_charset()

, a replacement of

nl_langinfo(CODESET)

.

6.6 Limit of Locale technology

Locale model has a limit. That is, it cannot handle two locales at the same time. Especially, it

cannot handle relationship between two locales at all.

For example, EUC JP, ISO 2022 JP, and Shift JIS are popular encodings in Japan. EUC JP is the

de facto standard for UNIX systems, ISO 2022 JP is the standard for Internet, and Shift JIS is the

encoding for Windows and Macintosh. Thus, Japanese people have to handle texts with these

encodings. Text viewers such as

jless

and

lv

and editors such as

emacs

can automatically

understand the encoding to be read. You cannot write such a software using Locale technology.