ipcserver and ipcclient are command-line tools for building local-domain
client-server applications. They conform to the UNIX Client-Server
Program Interface, UCSPI.

ipcserver listens for connections on a local-domain stream socket, and
runs a program for each connection it accepts. The program environment
includes variables that hold the local and remote socket addresses, and
the effective user and group IDs of the process that called connect.
ipcserver offers a concurrency limit on acceptance of new connections,
and selective handling of connections based on client identity.

ipcclient requests a connection to a local-domain socket, and runs a
program. The program environment includes a variable that holds the
local socket address.

ipcperl is an example of an ipchandle server. It invokes a perl
subroutine for each request.

WWW: http://www.superscript.com/ucspi-ipc/intro.html