| 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 is in a form suitable for parsing. |
| NLMSG_PAYLOAD() | Return the length of the payload associated with the nlmsghdr. |
NAME
netlink - Netlink macros
LIBRARY
Standard C library (libc, -lc)
SYNOPSIS
#include <asm/types.h>\n
\n#include <linux/netlink.h>int NLMSG_ALIGN(size_t \nlen\n);\n
\nint NLMSG_LENGTH(size_t \nlen\n);\n
\nint NLMSG_SPACE(size_t \nlen\n);\n
\nvoid *NLMSG_DATA(struct nlmsghdr *\nnlh\n);\n
\nstruct nlmsghdr *NLMSG_NEXT(struct nlmsghdr *\nnlh\n, int \nlen\n);\n
\nint NLMSG_OK(struct nlmsghdr *\nnlh\n, int \nlen\n);\n
\nint NLMSG_PAYLOAD(struct nlmsghdr *\nnlh\n, int \nlen\n);DESCRIPTION
<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 be accessed using only 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 is in a form suitable for parsing.
- NLMSG_PAYLOAD()
Return the length of the payload associated with the nlmsghdr.
VERSIONS
It is often better to use netlink via libnetlink than via the low-level kernel interface.
STANDARDS
Linux.
SEE ALSO
libnetlink(3), netlink(7)