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.   By default, the loopback interface is accessible at address 127.0.0.1 (non-standard); this address may be changed with the SIOCSIFADDR ioctl. 

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

intro(4N), inet(4F)

BUGS

It should handle all address and protocol families.  An approved network address should be reserved for this interface. 

4BSD