IP_ADD_MEMBERSHIP(2const) — Linux manual page

IP_ADD_MEMBERSHIP(2const)                       IP_ADD_MEMBERSHIP(2const)

NAME         top

       IP_ADD_MEMBERSHIP - join a multicast group

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

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

       int setsockopt(int sockfd, IPPROTO_IP, IP_ADD_MEMBERSHIP,
                      const struct ip_mreqn *val, sizeof(struct ip_mreqn));

DESCRIPTION         top

       Join a multicast group.

       IP_ADD_MEMBERSHIP is valid only for setsockopt(2).

ERRORS         top

       See IPPROTO_IP(2const).  See setsockopt(2).  See ip(7).

       EINVAL val->imr_multiaddr is not a valid multicast address.

HISTORY         top

       Linux 1.2.

       For compatibility, the old ip_mreq structure is still supported.
       The kernel determines which structure is being passed based on the
       size passed in the last argument.

SEE ALSO         top

       IPPROTO_IP(2const), ip_mreqn(2type), setsockopt(2), ip(7)

COLOPHON         top

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Linux man-pages 6.18            2025-11-25      IP_ADD_MEMBERSHIP(2const)

Pages that refer to this page: IP_ADD_SOURCE_MEMBERSHIP(2const),  IP_BLOCK_SOURCE(2const),  ip_mreqn(2type),  IP_MULTICAST_ALL(2const),  IPPROTO_IP(2const)

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