diff --git a/man7/epoll.7 b/man7/epoll.7
index acee70cf1..1d66a3583 100644
--- a/man7/epoll.7
+++ b/man7/epoll.7
@@ -352,6 +352,13 @@ data structure as removed and link it to a cleanup list. If you find another
 event for fd 13 in your batch processing, you will discover the fd had been
 previously removed and there will be no confusion.
 .SH CONFORMING TO
+The epoll API is Linux specific.  
+Some other systems provide similar
+mechanisms, e.g., FreeBSD has 
+.IR kqueue , 
+and Solaris has 
+.IR /dev/poll .
+.SH VERSIONS
 .BR epoll (7)
 is a new API introduced in Linux kernel 2.5.44.
 Its interface should be finalized in Linux kernel 2.5.66.