hpux man page for getsourcefilter

getsourcefilter(3N)													       getsourcefilter(3N)

NAME
       getsourcefilter() - get IP multicast source filter state

SYNOPSIS
DESCRIPTION
       This  function  retrieves the multicast source filter state for an IPv4 or IPv6 multicast group which the application has joined on a given
       socket.

   Parameters
       s	 Specifies the descriptor identifying the socket.  The socket address family must be or and the socket type must be

       interface Holds the interface index of a local interface, or zero.  If set to zero, the system chooses a multicast group  by  matching  the
		 multicast address only.

       group	 Points to either a sockaddr_in structure (for IPv4) or a sockaddr_in6 structure (for IPv6) that holds the IP multicast address of
		 the group.

       grouplen  Holds the size of the structure pointed to by the group argument.

       fmode	 Points to an integer that will contain the filter mode on a successful return.  The value of this field will be either  or  which
		 are defined in

       numsrc	 On input, the numsrc argument holds the number of source addresses that will fit in the slist array.  On output, the numsrc argu-
		 ment will hold the total number of sources in the filter.

       slist	 Points to buffer into which an array of sockaddr_storage structures containing the IP addresses of included or excluded  (depend-
		 ing  on  the  filter  mode) sources will be written.  The sockaddr_storage structures will contain either a sockaddr_in structure
		 (for IPv4 addresses) or a sockaddr_in6 structure (for IPv6 addresses, including IPv4-mapped IPv6 addresses); the  address  family
		 will match that of the group argument.  If numsrc was 0 on input, a NULL pointer may be supplied.

       If  the application does not know the size of the source list beforehand, it can make a reasonable guess (for example, by setting numsrc to
       0), and if upon completion, numsrc holds a larger value, the operation can be repeated with a large enough buffer.

       That is, on return, numsrc is always updated to be the total number of sources in  the  filter,	while  slist  will  hold  as  many  source
       addresses as fit, up to the minimum of the array size passed in as the original numsrc value and the total number of sources in the filter.

RETURN VALUES
       returns the following values:

	      Successful completion.

	      Failure.
		   is set to indicate the error.

ERRORS
       If fails, is set to one of the following values:

	      The argument	    s is not a valid descriptor.

	      This function is not supported by the socket type.

	      Insufficient memory is available for internal
				    system data structures.

	      The address family of the
				    group argument is not supported.

	      The specified multicast group has not been joined.

	      slist		    is NULL when numsrc is greater than 0; or group does not contain a multicast address; or interface contains an
				    invalid interface index; or grouplen is not valid.

AUTHOR
       was developed by HP and the IETF.

SEE ALSO
       socket(2), getipv4sourcefilter(3N), if_nameindex(3N), setipv4sourcefilter(3N), setsourcefilter(3N), ip(7P), ip6(7P).

STANDARDS CONFORMANCE
       RFC 3678

															       getsourcefilter(3N)