routine and family of routines may be used to manipulate this data.
.Pp
This option requires superuser privileges.
+.It Dv IPV6_TCLASS Fa "int *"
+Get or set the value of the traffic class field used for outgoing
+datagrams on this socket. The value must be between -1 and 255.
+A value of -1 resets to the default value.
+.It Dv IPV6_RECVTCLASS Fa "int *"
+Get or set the status of whether the traffic class header field
+will be provided as ancillary data along with the payload in subsequent
+.Xr recvmsg 2
+calls. The header field is stored as a single value of type int.
.It Dv IPV6_RTHDR Fa "int *"
Get or set whether the routing header from subsequent packets will be
provided as ancillary data along with the payload in subsequent
Get or set whether the minimal IPv6 maximum transmission unit (MTU) size
will be used to avoid fragmentation from occurring for subsequent
outgoing datagrams.
-.It Dv IPV6_AUTH_LEVEL Fa "int *"
-Get or set the
-.Xr ipsec 4
-authentication level.
-.It Dv IPV6_ESP_TRANS_LEVEL Fa "int *"
-Get or set the ESP transport level.
-.It Dv IPV6_ESP_NETWORK_LEVEL Fa "int *"
-Get or set the ESP encapsulation level.
-.It Dv IPV6_IPCOMP_LEVEL Fa "int *"
-Get or set the
-.Xr ipcomp 4
-level.
.El
.Pp
The