lo(7)                            (TCP/IP)                             lo(7)


   NAME
         lo - software loopback network interface

   SYNOPSIS
         d = open ("/dev/loop", ORDWR);

   DESCRIPTION
         The loopback device is a software datalink provider (interface
         driver) that returns all packets it receives to their source without
         involving any hardware devices.  It is a STREAMS device conforming to
         the datalink provider interface (DLPI).

         The loopback interface is used to access Internet services on the
         local machine.  Because it is available on all machines, including
         those with no hardware network interfaces, programs can use it for
         guaranteed access to local servers.  A typical application is the
         comsat(1M) server which accepts notification of mail delivery from a
         local client.  The loopback interface is also used for performance
         analysis and testing.

         By convention, the name of the loopback interface is lo0, and it is
         configured with Internet address 127.0.0.1.  This address may be
         changed with the SIOCSIFADDR ioctl().

   SEE ALSO
         comsat(1M), inet(7).



























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   lo(7)                            (TCP/IP)                             lo(7)


   NAME
         lo - software loopback network interface

   SYNOPSIS
         d = open ("/dev/loop", ORDWR);

   DESCRIPTION
         The loopback device is a software datalink provider (interface
         driver) that returns all packets it receives to their source without
         involving any hardware devices.  It is a STREAMS device conforming to
         the datalink provider interface (DLPI).  See if(7) for a general
         description of network interfaces.

         The loopback interface is used to access Internet services on the
         local machine.  Because it is available on all machines, including
         those with no hardware network interfaces, programs can use it for
         guaranteed access to local servers.  A typical application is the
         comsat(1M) server which accepts notification of mail delivery from a
         local client.  The loopback interface is also used for performance
         analysis and testing.

         By convention, the name of the loopback interface is lo0, and it is
         configured with Internet address 127.0.0.1.  This address may be
         changed with the SIOCSIFADDR ioctl().

   SEE ALSO
         comsat(1M), if(7), inet(7).


























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