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GETIFMADDRS(3)		     Library Functions Manual		  GETIFMADDRS(3)

NAME
     getifmaddrs -- get multicast group memberships

SYNOPSIS
     #include <ifaddrs.h>

     int
     getifmaddrs(struct ifmaddrs **ifmap);

     void
     freeifmaddrs(struct ifmaddrs *ifmp);

DESCRIPTION
     The  getifmaddrs() function stores a reference to a linked list of the mul-
     ticast memberships on the local machine in the memory referenced by  ifmap.
     The  list	consists  of ifmaddrs structures, as defined in the include file
     <ifaddrs.h>.  The ifmaddrs structure contains at least  the  following  en-
     tries:

	 struct ifmaddrs   *ifma_next;	   /* Pointer to next struct */
	 struct sockaddr   *ifma_name;	   /* Interface name (AF_LINK) */
	 struct sockaddr   *ifma_addr;	   /* Multicast address */
	 struct sockaddr   *ifma_lladdr;   /* Link-layer translation, if any */

     The  ifma_next  field contains a pointer to the next structure on the list.
     This field is NULL in last structure on the list.

     The ifma_name field references an AF_LINK address structure, containing the
     name of the interface where the membership exists.

     The ifma_addr references the address that this membership is for.

     The ifma_lladdr field references a link-layer translation for the protocol-
     level address in ifma_addr, if one is set, otherwise it is NULL.

     The data returned by getifmaddrs() is dynamically allocated and  should  be
     freed using freeifmaddrs() when no longer needed.

RETURN VALUES
     The getifmaddrs() function returns the value 0 if successful; otherwise the
     value  -1	is returned and the global variable errno is set to indicate the
     error.

ERRORS
     The getifmaddrs() may fail and set errno for any of  the  errors  specified
     for the library routines malloc(3) or sysctl(3).

SEE ALSO
     sysctl(3), networking(4), ifconfig(8)

HISTORY
     The getifmaddrs() function first appeared in FreeBSD 5.2.

BUGS
     If  both  <net/if.h> and <ifaddrs.h> are being included, <net/if.h> must be
     included before <ifaddrs.h>.

FreeBSD 14.3			  May 21, 2013			  GETIFMADDRS(3)

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