dev_set_allmulti(9) centos man page | unix.com

DEV_SET_ALLMULTI(9)					      Network device support					       DEV_SET_ALLMULTI(9)

NAME
       dev_set_allmulti - update allmulti count on a device

SYNOPSIS
       int dev_set_allmulti(struct net_device * dev, int inc);

ARGUMENTS
       dev
	   device

       inc
	   modifier

DESCRIPTION
       Add or remove reception of all multicast frames to a device. While the count in the device remains above zero the interface remains
       listening to all interfaces. Once it hits zero the device reverts back to normal filtering operation. A negative inc value is used to drop
       the counter when releasing a resource needing all multicasts. Return 0 if successful or a negative errno code on error.

COPYRIGHT
Kernel Hackers Manual 3.10					     June 2014						       DEV_SET_ALLMULTI(9)