nn_cmsg(3)
==========

NAME
----
nn_cmsg - access control information


SYNOPSIS
--------
*#include <nanomsg/nn.h>*

*struct nn_cmsghdr *NN_CMSG_FIRSTHDR(struct nn_msghdr '*hdr');*

*struct nn_cmsghdr *NN_CMSG_NXTHDR(struct nn_msghdr '*hdr', struct nn_cmsghdr '*cmsg');*

*unsigned char *NN_CMSG_DATA(struct nn_cmsghdr '*cmsg');*

*size_t NN_CMSG_SPACE(size_t 'len');*

*size_t NN_CMSG_LEN(size_t 'len');*

DESCRIPTION
-----------

_NN_CMSG_FIRSTHDR_ returns a pointer to the first nn_cmsghdr in the control buffer in the supplied nn_msghdr structure.

_NN_CMSG_NXTHDR_ returns the next nn_cmsghdr after the supplied nn_cmsghdr. Returns NULL if there isn't enough space in the buffer.

_NN_CMSG_DATA_ returns a pointer to the data associated with supplied nn_cmsghdr.

_NN_CMSG_SPACE_ returns the number of bytes occupied by nn_cmsghdr with payload of the specified length.

_NN_CMSG_LEN_ returns the value to store in the cmsg_len member of the cmsghdr structure, taking into account any  necessary  alignment.


SEE ALSO
--------
linknanomsg:nn_sendmsg[3]
linknanomsg:nn_recvmsg[3]
linknanomsg:nanomsg[7]


AUTHORS
-------
Martin Sustrik <sustrik@250bpm.com>