BUGS: In kernels < 2.6.9, EPOLL_CTL_DEL required a non-NULL

'event', even though this argument is ignored.
As per http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=306517.

man2/epoll_ctl.2

@@ -31,7 +31,7 @@ Control an
 .B epoll
 descriptor,
 .IR epfd ,
-by requesting the operation
+by requesting that the operation
 .IR op
 be performed on the target file descriptor,
 .IR fd .
@@ -44,7 +44,6 @@ The
 is defined as :
 .sp
 .nf
-
 	typedef union epoll_data {
 		void *ptr;
 		int fd;
@@ -56,7 +55,6 @@ is defined as :
 		__uint32_t events;	/* Epoll events */
 		epoll_data_t data;	/* User data variable */
 	};
-
 .fi
 
 The
@@ -101,8 +99,8 @@ for more detailed information about Edge and Level Triggered event
 distribution architectures.
 .TP
 .B EPOLLONESHOT
-Sets the one-shot behaviour for the associated file descriptor. It means
-that after an event is pulled out with
+Sets the one-shot behaviour for the associated file descriptor.
+This means that after an event is pulled out with
 .BR epoll_wait (2)
 the associated file descriptor is internally disabled and no other events
 will be reported by the
@@ -113,7 +111,6 @@ with
 .B EPOLL_CTL_MOD
 to re-enable the file descriptor with a new event mask.
 .PP
-.sp
 The
 .B epoll
 interface supports all file descriptors that support
@@ -150,7 +147,7 @@ file descriptor,
 .IR epfd .
 The
 .IR event
-is ignored and can be NULL.
+is ignored and can be NULL (but see BUGS below).
 .RE
 .SH "RETURN VALUE"
 When successful, 
@@ -207,6 +204,17 @@ does not support
 .BR epoll_ctl (2)
 is a new API introduced in Linux kernel 2.5.44.
 The interface should be finalized by Linux kernel 2.5.66.
+.SH BUGS
+In kernel versions before 2.6.9, the
+.B EPOLL_CTL_DEL
+operation required a non-NULL pointer in 
+.IR event ,
+even though this argument is ignored.
+Since kernel 2.6.9,
+.I event
+can be specified as NULL
+when using 
+.BR EPOLL_CTL_DEL .
 .SH "SEE ALSO"
 .BR epoll_create (2),
 .BR epoll_wait (2),