-.TH libnetlink 3
-.SH NAME
-libnetlink \- A library for accessing the netlink service
-.SH SYNOPSIS
-.nf
-#include <asm/types.h>
-.br
-#include <libnetlink.h>
-.br
-#include <linux/netlink.h>
-.br
-#include <linux/rtnetlink.h>
-.sp
-int rtnl_open(struct rtnl_handle *rth, unsigned subscriptions)
-.sp
-int rtnl_wilddump_request(struct rtnl_handle *rth, int family, int type)
-.sp
-int rtnl_send(struct rtnl_handle *rth, char *buf, int len)
-.sp
-int rtnl_dump_request(struct rtnl_handle *rth, int type, void *req, int len)
-.sp
-int rtnl_dump_filter(struct rtnl_handle *rth,
- int (*filter)(struct sockaddr_nl *, struct nlmsghdr *n, void *),
- void *arg1,
- int (*junk)(struct sockaddr_nl *,struct nlmsghdr *n, void *),
- void *arg2)
-.sp
-int rtnl_talk(struct rtnl_handle *rtnl, struct nlmsghdr *n, pid_t peer,
- unsigned groups, struct nlmsghdr *answer,
-.br
- int (*junk)(struct sockaddr_nl *,struct nlmsghdr *n, void *),
-.br
- void *jarg)
-.sp
-int rtnl_listen(struct rtnl_handle *rtnl,
- int (*handler)(struct sockaddr_nl *,struct nlmsghdr *n, void *),
- void *jarg)
-.sp
-int rtnl_from_file(FILE *rtnl,
- int (*handler)(struct sockaddr_nl *,struct nlmsghdr *n, void *),
- void *jarg)
-.sp
-int addattr32(struct nlmsghdr *n, int maxlen, int type, __u32 data)
-.sp
-int addattr_l(struct nlmsghdr *n, int maxlen, int type, void *data, int alen)
-.sp
-int rta_addattr32(struct rtattr *rta, int maxlen, int type, __u32 data)
-.sp
-int rta_addattr_l(struct rtattr *rta, int maxlen, int type, void *data, int alen)
-.SH DESCRIPTION
-libnetlink provides a higher level interface to
-.BR rtnetlink(7).
-The read functions return 0 on success and a negative errno on failure.
-The send functions return the amount of data sent, or -1 on error.
-.TP
-rtnl_open
-Open a rtnetlink socket and save the state into the
-.B rth
-handle. This handle is passed to all subsequent calls.
-.B subscriptions
-is a bitmap of the rtnetlink multicast groups the socket will be
-a member of.
-
-.TP
-rtnl_wilddump_request
-Request a full dump of the
-.B type
-database for
-.B family
-addresses.
-.B type
-is a rtnetlink message type.
-.\" XXX
-
-.TP
-rtnl_dump_request
-Request a full dump of the
-.B type
-data buffer into
-.B buf
-with maximum length of
-.B len.
-.B type
-is a rtnetlink message type.
-
-.TP
-rtnl_dump_filter
-Receive netlink data after a request and filter it.
-The
-.B filter
-callback checks if the received message is wanted. It gets the source
-address of the message, the message itself and
-.B arg1
-as arguments. 0 as return means that the filter passed, a negative
-value is returned
-by
-.I rtnl_dump_filter
-in case of error. NULL for
-.I filter
-means to not use a filter.
-.B junk
-is used to filter messages not destined to the local socket.
-Only one message bundle is received. Unless there is no message
-pending, this function does not block.
-
-.TP
-rtnl_listen
-Receive netlink data after a request and pass it to
-.I handler.
-.B handler
-is a callback that gets the message source address, the message itself,
-and the
-.B jarg
-cookie as arguments. It will get called for all received messages.
-Only one message bundle is received. Unless there is no message
-pending this function does not block.
-
-.TP
-rtnl_from_file
-Works like
-.I rtnl_listen,
-but reads a netlink message bundle from the file
-.B file
-and passes the messages to
-.B handler
-for parsing. The file contains raw data as received from a rtnetlink socket.
-.PP
-The following functions are useful to construct custom rtnetlink messages. For
-simple database dumping with filtering it is better to use the higher level
-functions above. See
-.BR rtnetlink(3)
-and
-.BR netlink(3)
-on how to generate a rtnetlink message. The following utility functions
-require a continuous buffer that already contains a netlink message header
-and a rtnetlink request.
-
-.TP
-rtnl_send
-Send the rtnetlink message in
-.B buf
-of length
-.B len
-to handle
-.B rth.
-
-.TP
-addattr32
-Add a __u32 attribute of type
-.B type
-and with value
-.B data
-to netlink message
-.B n,
-which is part of a buffer of length
-.B maxlen.
-
-.TP
-addattr_l
-Add a variable length attribute of type
-.B type
-and with value
-.B data
-and
-.B alen
-length to netlink message
-.B n,
-which is part of a buffer of length
-.B maxlen.
-.B data
-is copied.
-
-.TP
-rta_addattr32
-Initialize the rtnetlink attribute
-.B rta
-with a __u32 data value.
-
-.TP
-rta_addattr32
-Initialize the rtnetlink attribute
-.B rta
-with a variable length data value.
-
-.SH BUGS
-The functions sometimes use fprintf and exit when a fatal error occurs.
-This library should be named librtnetlink.
-
-.SH AUTHORS
-netlink/rtnetlink was designed and writen by Alexey Kuznetsov.
-Andi Kleen wrote the man page.
-
-.SH SEE ALSO
-.BR netlink(7),
-.BR rtnetlink(7)
-.br
-/usr/include/linux/rtnetlink.h