ip_mreqn(2type) — Linux manual page

ip_mreqn(2type)                                           ip_mreqn(2type)

NAME         top

       ip_mreqn, ip_mreq - IP multicast request index

LIBRARY         top

       Standard C library (libc)

SYNOPSIS         top

       #include <netinet/in.h>  /* Definition of IP* constants */

       struct ip_mreqn {
           struct in_addr  imr_multiaddr;  /* IP multicast group address */
           struct in_addr  imr_address;    /* IP address of local interface */
           int             imr_ifindex;    /* interface index */
       };

       struct ip_mreq {
           struct in_addr  imr_multiaddr;  /* IP multicast group address */
           struct in_addr  imr_address;    /* IP address of local interface */
       };

DESCRIPTION         top

       .imr_multiaddr
              The address of the multicast group the application wants to
              join or leave.  It must be a valid multicast address.

       .imr_address
              The address of the local interface with which the system
              should join the multicast group; if it is equal to
              INADDR_ANY, an appropriate interface is chosen by the
              system.

       .imr_ifindex
              The interface index of the interface that should join/leave
              the .imr_multiaddr group, or 0 to indicate any interface.

HISTORY         top

       ip_mreqn
              Linux 2.2.

       ip_mreq
              Linux 1.2.

SEE ALSO         top

       IP_ADD_MEMBERSHIP(2const), IP_DROP_MEMBERSHIP(2const),
       IP_MULTICAST_IF(2const), ip(7)

COLOPHON         top

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Linux man-pages 6.18            2025-11-25                ip_mreqn(2type)

Pages that refer to this page: IP_ADD_MEMBERSHIP(2const),  IP_DROP_MEMBERSHIP(2const),  ip_mreq_source(2type),  IP_MULTICAST_IF(2const)

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