LO(4) 1990 LO(4) NNAAMMEE lo - software loopback network interface SSYYNNOOPPSSIISS ppsseeuuddoo--ddeevviiccee lloooopp DDEESSCCRRIIPPTTIIOONN The _l_o_o_p interface is a software loopback mechanism which may be used for performance analysis, software testing, and/or local communication. As with other network inter- faces, the loopback interface must have network addresses assigned for each address family with which it is to be used. These addresses may be set or changed with the SIOC- SIFADDR ioctl. The loopback interface should be the last interface configured, as protocols may use the order of con- figuration as an indication of priority. The loopback should nneevveerr be configured first unless no hardware inter- faces exist. DDIIAAGGNNOOSSTTIICCSS lloo%%dd:: ccaann''tt hhaannddllee aaff%%dd. The interface was handed a message with addresses formatted in an unsuitable address family; the packet was dropped. SSEEEE AALLSSOO intro(4), inet(4), ns(4) BBUUGGSS Previous versions of the system enabled the loopback inter- face automatically, using a nonstandard Internet address (127.1). Use of that address is now discouraged; a reserved host address for the local network should be used instead. Printed 7/27/90 June 1