Why is getaddrinfo breaking POSIX?

[Jonathan Schleifer]

Just wondering: Why is getaddrinfo breaking POSIX by not being thread- 
safe and what is the thread-safe alternative to it? (Please don't tell  
me to use locks, as that would kill the possibility to lookup multiple  
hosts at once).

I consider it very strange that an OS still has a thread-unsafe  
getaddrinfo in the year 2009, even though POSIX and RFC 2553 both  
require it to be thread-safe. And it makes it especially hard to write  
portable applications, as there is no way to check if getaddrinfo is  
thread-safe in a configure script.

--
Jonathan