1This is latd - a LAT terminal daemon for Linux and BSD. It provides the
2following features:
3
4- Provides LAT login services (you can log onto Linux from a DECserver)
5- Can have multiple login services with different service ratings
6- Static and dynamic service ratings are supported
7- Provides Reverse-LAT. "devices" in /dev/lat/ can be used to connect to
8  advertised services on DECservers or VMS/Tru64 hosts
9- Provides queueing facility for reverse LAT ports. Useful for printers
10- Can provide a node responder service for small-memory DECservers
11- Full featured latcp control program - most internal parameters can be
12  changed on the fly
13- A script is run at daemon startup to provide customisation
14- man pages for all programs and config files
15- Group codes can be used for to restrict incoming and outgoing sessions
16- User-space daemon. No kernel patching or recompiling necessary
17- Does not need DECnet support from the kernel or libraries
18- Supports a group called "lat" to restrict users of reverse-LAT ports
19- llogin program so users can log into LAT services
20- moprc for remote management for terminal servers.
21- To send BREAK to a remote server in a reverse-LAT session press ^@
22
23For Linux you will need Packet Socket support in the kernel, but I think that's
24usually the default anyway. BSD systems use the Berkeley Packet Filter.
25Although Linux also has a BPF, latd cannot use it.
26
27This software will not work on Linux kernels 2.0 or lower.
28
29You should start latd with the latcp -s command. Starting latd manually is not
30supported and may result in unexpected behaviour. See the man page for latcp
31for more information.
32
33This code is a clean-room reverse-engineering effort. I have no access to
34HP technical documentation or source code for LAT and nor do I want any.
35
36This software should work on all architectures supported by the target
37operating systems. I have tested it on Intel, Alpha, SPARC, MIPS, PA-RISC and
38PowerPC.
39
40SUPPORTED SYSTEMS
41-----------------
42LATD itself runs on Linux and several BSD systems: NetBSD, FreeBSD and Darwin
43have been tested. Not all the ports are tested very thoroughly, as I primarily
44use Linux and Darwin.
45
46The following systems I know to work on the other end of LATD because I have
47tested them, others may also work.
48
49OpenVMS 7.2 & 7.3 (VAX & Alpha)
50DEC Unix v4.0d
51DECserver 200/MC
52DECserver 90M
53DECserver 90L+
54DECserver 700
55
56COMPILING
57---------
58LAT uses GNU autoconf to configure and build so all you should need to
59do is
60
61./configure && make
62
63to compile, and
64
65make install
66
67to install
68
69There are several things you can tweak in the configuration process:
70
71--enable-debug   Build a debug binary that does not daemonise itself
72                 and issues lots of loggin messages to stderr
73--with-login     Sets the login program to use for incoming connections. This
74                 defaults to the local login program (/bin/login or
75                 /usr/bin/login). If you want to disable logins you can either
76                 use --with-login=/bin/false or add "$LATCP -D -a `uname -n`"
77                 to latd.conf
78--prefix         Sets where the binaries are installed
79                (default /usr/local)
80--sysconfdir     Sets where the config file is kept
81                 (default is /usr/local again)
82                 Note that if you set --prefix to /usr, you will probably
83                 also want to set --sysconfdir to / so that the config
84                 file goes in /etc rather than /usr/etc
85
86PRINTING
87--------
88You can use latd and Linux as a printer server. See latprint.sh for
89for more information.
90
91CREDITS
92-------
93The BPF interface used in the *BSD ports was written by Matthew Fredette
94(fredette@netbsd.org), as was much of the autoconf system.
95
96I'd like to thank Eduardo Serrat for providing much help, trace logs
97and encouragement in this reverse-engineering effort.
98
99I am also very much indebted to Real Dupeux for sending me a DECserver 200
100for the project, without which it would be much impoverished.
101
102I would also like to express gratitude to ABB for providing a DECserver 90M and
103to Rob Davies for DECserver 90L+s.
104