Discussion on:

Use sendfile() to optimize data transfer

On Solaris 8, patch 111297-01 (or later) will add support for sendfilev

sendfilev is also a very handy function on solaris.
it allows you to mix memory buffers and file handles so that you can send a HTML response with some dynamic parts (which would be in a memory buffer) and a static parts (which could be pointed tobe a file handle)..
this may be the most efficent way of sending a semi-dynamic page

Sendfile() is a relatively new operating system kernel primitive, which was introduced to solve the aforementioned problems. It is available in the latest kernel editions (UNIX, Linux, Solaris 8).

:=> How about FreeBSD (4.2) ??