DCCP_SOCKOPT_GET_CUR_MPS is read-only and retrieves the current maximum packet
size (application payload size) in bytes, see RFC 4340, section 14.
+DCCP_SOCKOPT_SERVER_TIMEWAIT enables the server (listening socket) to hold
+timewait state when closing the connection (RFC 4340, 8.3). The usual case is
+that the closing server sends a CloseReq, whereupon the client holds timewait
+state. When this boolean socket option is on, the server sends a Close instead
+and will enter TIMEWAIT. This option must be set after accept() returns.
+
DCCP_SOCKOPT_SEND_CSCOV and DCCP_SOCKOPT_RECV_CSCOV are used for setting the
partial checksum coverage (RFC 4340, sec. 9.2). The default is that checksums
always cover the entire packet and that only fully covered application data is
sequence-invalid packets on the same socket (RFC 4340, 7.5.4). The unit
of this parameter is milliseconds; a value of 0 disables rate-limiting.
+IOCTLS
+======
+FIONREAD
+ Works as in udp(7): returns in the `int' argument pointer the size of
+ the next pending datagram in bytes, or 0 when no datagram is pending.
+
Notes
=====