IDNA and getnameinfo() and getaddrinfo()

Simon Josefsson simon at
Mon Jun 14 22:33:48 CEST 2010

Dave Thaler <dthaler at> writes:

> RFC 3493 doesn't say either way whether "char *" is ANSI or UTF-8 or whatever
> else, and as far as I know, neither does POSIX 
> (

Normally in POSIX, strings are encoded in the locale coding system.  If
you are in a UTF-8 locale, the string can be assumed (by the getaddrinfo
implementation) to be UTF-8.  Otherwise it needs to be transcoded.  This
is how GNU Libc's IDN support works, see:


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