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Add missing markup bits.

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This commit is contained in:
Ruslan Ermilov 2003-05-20 22:07:55 +00:00
parent 351ed10fd4
commit 8d22ff7521
1 changed files with 46 additions and 21 deletions
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67
share/man/man4/ip.4
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@ -125,11 +125,19 @@ call will return the destination
address for a
.Tn UDP
datagram.
The msg_control field in the msghdr structure points to a buffer
that contains a cmsghdr structure followed by the
The
.Vt msg_control
field in the
.Vt msghdr
structure points to a buffer
that contains a
.Vt cmsghdr
structure followed by the
.Tn IP
address.
The cmsghdr fields have the following values:
The
.Vt cmsghdr
fields have the following values:
.Bd -literal
cmsg_len = sizeof(struct in_addr)
cmsg_level = IPPROTO_IP
@ -143,7 +151,9 @@ datagrams on a socket that is not bound to a specific
address can be specified as ancillary data with a type code of
.Dv IP_SENDSRCADDR .
The msg_control field in the msghdr structure should point to a buffer
that contains a cmsghdr structure followed by the
that contains a
.Vt cmsghdr
structure followed by the
.Tn IP
address.
The cmsghdr fields should have the following values:
@ -177,7 +187,7 @@ call will return the
.Tn UDP
datagram.
The msg_control field in the msghdr structure points to a buffer
that contains a cmsghdr structure followed by the
that contains a cmsghdr structure followed by the
.Tn TTL .
The cmsghdr fields have the following values:
.Bd -literal
@ -186,16 +196,27 @@ cmsg_level = IPPROTO_IP
cmsg_type = IP_RECVTTL
.Ed
.Pp
If the
.Dv IP_RECVIF
option is enabled on a
If the
.Dv IP_RECVIF
option is enabled on a
.Dv SOCK_DGRAM
socket, the
.Xr recvmsg 2
call returns a struct sockaddr_dl corresponding to the interface on which the
packet was received. The msg_control field in the msghdr structure points
to a buffer that contains a cmsghdr structure followed by the
struct sockaddr_dl. The cmsghdr fields have the following values:
socket, the
.Xr recvmsg 2
call returns a
.Vt "struct sockaddr_dl"
corresponding to the interface on which the
packet was received.
The
.Va msg_control
field in the
.Vt msghdr
structure points to a buffer that contains a
.Vt cmsghdr
structure followed by the
.Vt "struct sockaddr_dl" .
The
.Vt cmsghdr
fields have the following values:
.Bd -literal
cmsg_len = sizeof(struct sockaddr_dl)
cmsg_level = IPPROTO_IP
@ -230,7 +251,8 @@ and
use a low range of ports, which are normally restricted to
privileged processes on
.Ux
systems. The range is normally from
systems.
The range is normally from
.Dv IPPORT_RESERVED
\- 1 down to
.Li IPPORT_RESERVEDSTART
@ -287,7 +309,8 @@ Datagrams with a TTL of 1 are not forwarded beyond the local network.
Multicast datagrams with a TTL of 0 will not be transmitted on any network,
but may be delivered locally if the sending host belongs to the destination
group and if multicast loopback has not been disabled on the sending socket
(see below). Multicast datagrams with TTL greater than 1 may be forwarded
(see below).
Multicast datagrams with TTL greater than 1 may be forwarded
to other networks if a multicast router is attached to the local network.
.Pp
For hosts with multiple interfaces, each multicast transmission is
@ -329,18 +352,20 @@ setsockopt(s, IPPROTO_IP, IP_MULTICAST_LOOP, &loop, sizeof(loop));
This option
improves performance for applications that may have no more than one
instance on a single host (such as a router daemon), by eliminating
the overhead of receiving their own transmissions. It should generally not
the overhead of receiving their own transmissions.
It should generally not
be used by applications for which there may be more than one instance on a
single host (such as a conferencing program) or for which the sender does
not belong to the destination group (such as a time querying program).
.Pp
A multicast datagram sent with an initial TTL greater than 1 may be delivered
to the sending host on a different interface from that on which it was sent,
if the host belongs to the destination group on that other interface. The
loopback control option has no effect on such delivery.
if the host belongs to the destination group on that other interface.
The loopback control option has no effect on such delivery.
.Pp
A host must become a member of a multicast group before it can receive
datagrams sent to the group. To join a multicast group, use the
datagrams sent to the group.
To join a multicast group, use the
.Dv IP_ADD_MEMBERSHIP
option:
.Bd -literal
@ -487,7 +512,7 @@ The following errors specific to
may occur when setting or getting
.Tn IP
options:
.Bl -tag -width EADDRNOTAVAILxx
.Bl -tag -width Er
.It Bq Er EINVAL
An unknown socket option name was given.
.It Bq Er EINVAL