| NAME | SYNOPSIS | DESCRIPTION | CONFORMING TO | NOTES | SEE ALSO | COLOPHON | The Linux Programming Interface |
NETLINK(3) Linux Programmer's Manual NETLINK(3)
netlink - Netlink macros
#include <asm/types.h>
#include <linux/netlink.h>
int NLMSG_ALIGN(size_t len);
int NLMSG_LENGTH(size_t len);
int NLMSG_SPACE(size_t len);
void *NLMSG_DATA(struct nlmsghdr *nlh);
struct nlmsghdr *NLMSG_NEXT(struct nlmsghdr *nlh, int len);
int NLMSG_OK(struct nlmsghdr *nlh, int len);
int NLMSG_PAYLOAD(struct nlmsghdr *nlh, int len);
<linux/netlink.h> defines several standard macros to access or create a
netlink datagram. They are similar in spirit to the macros defined in cmsg(3)
for auxiliary data. The buffer passed to and from a netlink socket should
only be accessed using these macros.
NLMSG_ALIGN()
Round the length of a netlink message up to align it properly.
NLMSG_LENGTH()
Given the payload length, len, this macro returns the aligned length to
store in the nlmsg_len field of the nlmsghdr.
NLMSG_SPACE()
Return the number of bytes that a netlink message with payload of len
would occupy.
NLMSG_DATA()
Return a pointer to the payload associated with the passed nlmsghdr.
NLMSG_NEXT()
Get the next nlmsghdr in a multipart message. The caller must check if
the current nlmsghdr didn't have the NLMSG_DONE set -- this function
doesn't return NULL on end. The len argument is an lvalue containing
the remaining length of the message buffer. This macro decrements it
by the length of the message header.
NLMSG_OK()
Return true if the netlink message is not truncated and ok to parse.
NLMSG_PAYLOAD()
Return the length of the payload associated with the nlmsghdr.
These macros are nonstandard Linux extensions.
It is often better to use netlink via libnetlink than via the low-level kernel
interface.
netlink(7)
and ftp://ftp.inr.ac.ru/ip-routing/iproute2* for libnetlink
This page is part of release 3.32 of the Linux man-pages project. A
description of the project, and information about reporting bugs, can be found
at http://www.kernel.org/doc/man-pages/.
GNU 1999-05-14 NETLINK(3)
HTML rendering created 2010-12-03 by Michael Kerrisk, author of The Linux Programming Interface