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IP_MULTICAST_ALL(2const) — Linux manual page

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | ERRORS | HISTORY | SEE ALSO | COLOPHON 

IP_MULTICAST_ALL(2const)                         IP_MULTICAST_ALL(2const)

NAME         top

       IP_MULTICAST_ALL - delivery policy of multicast messages

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_MULTICAST_ALL,
                      const int *val, sizeof(int));

DESCRIPTION         top

       This option can be used to modify the delivery policy of multicast
       messages.

       If set to 1 (default), the socket will receive messages from all
       the groups that have been joined globally on the whole system.

       If set to 0, it will deliver messages only from the groups that
       have been explicitly joined (for example via
       IP_ADD_MEMBERSHIP(2const)) on this particular socket.

ERRORS         top

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

HISTORY         top

       Linux 2.6.31.

SEE ALSO         top

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

COLOPHON         top

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

Pages that refer to this page: IPPROTO_IP(2const)

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