LO(4) — Unix Programmer’s Manual
NAME
lo − software loopback network interface
SYNOPSIS
pseudo-device loop
DESCRIPTION
The loop interface is a software loopback mechanism which may be used for performance analysis, software testing, and/or local communication. The loopback interface is accessible as network 127 (non-standard).
DIAGNOSTICS
lo%d: can’t handle af%d. The interface was handed a message with addresses formatted in an unsuitable address family; the packet was dropped.
SEE ALSO
BUGS
It should handle all address and protocol families. An approved network address should be reserved for this interface.
4th Berkeley Distribution — 26 March 1982