preadv() sys call missing

[dslowik2]

I have Ubuntu 10.10 up to date. It is missing the man page for preadv() pwritev() system calls (section 2 of man pages).
Shouuldn't I have the man page if i have the function? And where to get the man page?

[dslowik2]

http://manpages.ubuntu.com/cgi-bin/search.py?q=man&titles=Title
Provides man pages online.