WARNING: If you are upgrading an existing LambdaMOO database from an earlier version of the server, you should read the relevant notes in ChangeLog.txt regarding DB changes you may need to make before doing the upgrade. Such notes are marked in ChangeLog.txt with the string `NOTE'.
Getting Started With LambdaMOO
LambdaMOO has been successfully compiled and tested on several machines and operating systems; a table appears at the end of this file.
People compiling on any of these machines should only need to do the following: -- run the command `sh configure'; it will take a couple of minutes, trying
out various features of your operating system, figuring out which of a
long list of known quirks must be patched around for your system. It will
produce a fair amount of output as it runs, every line of it beginning
with the word `checking'. When it's finished poking at your system, it
will print out a little note concerning which networking options will work
on your particular machine. Make a note of these, since they'll constrain
your choice of edits in the next step.
-- edit the file `options.h', choosing the options appropriate to your needs
and your local configuration. In particular, this is where you specify
the kind of networking the server should support, choosing from the
options printed by `configure' in the first step.
-- type `make'; the code should compile with almost no errors or warnings.
The exception is warnings about code in files from your own system;
an amazing number of systems contain header files and other files that
don't compile without warnings. Obviously, I can't do anything about
these files, so just ignore such warnings.
That should do it, you'll now have a working LambdaMOO server.
[EXCEPTION: If you've defined NETWORK_PROTOCOL to be NP_LOCAL in
`options.h', then you will also need a specialized client program
for connecting to the server. Type either `make client_bsd' or
`make client_sysv', depending on how you defined NETWORK_STYLE, to
create the appropriate client program.]
If you're not on one of these configurations, you may still get lucky. You will need the following things:
-- You need a C compiler that is at least mostly compliant with the ANSI C
standard. Old-style, purely Kernighan & Ritchie compilers will fail
miserably. The more closely it adheres to the standard, the less trouble
you'll have.
-- You need support for signals, forking, and pausing, preferably according
to the POSIX standard; if you haven't got POSIX, then I might be ready for
your particular non-standard system anyway.
-- You need an implementation of the crypt() password-encryption function
that comes with all BSD UNIX operating systems.
If you've got all of this, then try the above procedure (i.e., type `sh configure', edit `options.h', and type `make') and there's a good chance that it will just work. If so, please let me know so that I can add your machine and operating system to the table at the end of this file. If not, feel free to send me mail and I'll help you try to make it work.
To start the server, use a command like this:
./moo INITIAL-DB-FILE CHECKPOINT-DB-FILE
where INITIAL-DB-FILE is the name of an existing LambdaMOO database file and CHECKPOINT-DB-FILE is the filename the server should use for its periodic checkpoints of the current DB, which is otherwise kept only in its memory. IT IS STRONGLY ADVISED that you not use the same file name for both INITIAL-DB-FILE and CHECKPOINT-DB-FILE; this could, in the event of a crash, leave you with no useful DB file at all.
Included with the release is a little shell script called `scripts/restart.sh' that handles the server start-up in a more convenient way. You type a command like
./scripts/restart.sh FOOBAR
and the script does the following:
-- If FOOBAR.db.new exists, then
+ Rename FOOBAR.db to FOOBAR.db.old, and start a background process to
compress that file.
+ Rename FOOBAR.db.new to FOOBAR.db
-- Start the server in the background, reading the initial DB from FOOBAR.db
and writing the checkpoints to FOOBAR.db.new. The server's log of network
connections, checkpoints, and errors will be put into FOOBAR.log. If
there was already a file named FOOBAR.log, its old contents are appended
to FOOBAR.log.old and FOOBAR.log is removed first.
The `restart' script is really the only good way to start up the server; it's all I ever use for LambdaMOO itself.
If your server gets a lot of use and your users start getting the error message
*** Sorry, but the server cannot accept any more connections right now.
*** Please try again later.
when they try to connect, it's because your server has run out of UNIX file
descriptors. If you'd like to allow more folks to connect, you'll have to bump
up the limit (though there's a hard limit in the UNIX kernel that you won't be
able to exceed). To bump up the limit as far as it will go, remove the `#' at
the beginning of the line
#unlimit descriptors
in the `restart' script before starting up your server.
For most of the networking options supported by the server, both the `moo' and `restart' commands take an optional argument for changing some network connection information; type just `./moo' to see what the argument is for the option you've chosen. The only one for which you're at all likely to want to override the default concerns the NP_TCP networking options; for them, the optional argument is the TCP port number on which the server should listen for new connections (the default is 7777).
The `moo' command can take an optional first argument `-e'; if provided, the server does not start accepting connections immediately after loading the database file. Instead, using its standard input and output streams, it enters `emergency wizard mode', in which you can list and (re)set verb programs, execute MOO expressions and programs, etc. This mode is useful for recovering from having made terrible mistakes in the database, perhaps by reprogramming crucial verbs in such a way as to make it impossible to log in as usual. Type `help' in this mode to see a complete list of available emergency commands.
The only database included with the release is Minimal.db. Getting from there to something usable is possible, but tedious; see README.Minimal for details.
Also available for FTP from ftp ftp.parc.xerox.com is a version of LambdaCore.db, a snapshot of the core pieces of the LambdaMOO database. New snapshots are made at irregular intervals as sufficient changes happen to the LambdaMOO database.
The LambdaMOO Programmer's Manual is also available for FTP from the same place. It comes in plain-text, Texinfo, and Postscript formats.
Once the database has been loaded, the server reacts to various standard UNIX process signals as follows:
Signal(s) Action
--------- ------
FPE Ignored
HUP (if it was already Ignored
being ignored)
HUP (otherwise) Reopen log file
ILL, QUIT, SEGV, BUS Panic the server
INT, TERM, USR1 Shut down the server cleanly
USR2 Schedule a checkpoint ASAP
For the most part, this just means that the following commands might be useful to you:
kill -INT <server-pid> Cleanly shut down the server
kill -USR2 <server-pid> Make the server write a checkpoint soon
If you're using an NP_TCP networking configuration, then if you do a `ps' command you should see either three or four UNIX processes concerned with the running server. The one with the lowest process number (probably) is the main server itself, the program that's actually executing MOO commands, etc. The next two processes are associated with the way the MOO server does lookups of network host names; by using extra (smallish) processes for this, the server can robustly recover from nameserver flakiness. The fourth process is only present from time to time; it is a copy of the main server process that is `checkpointing,' writing out a copy of the database into a file. On many systems (wherever possible), the server changes the output of the `ps' command to show you explicitly which of these processes is which.
Finally, if you're putting up a LambdaMOO server, you should probably be a member of the MOO-Cows mailing list. Send email to MOO-Cows-Request@Xerox.Com saying just `subscribe' to get yourself added to the list.
Pavel Curtis
aka Lambda
aka Haakon
Archwizard of LambdaMOO
Pavel@Xerox.Com
How to Add New Built-In Functions to the MOO Language
Implement your functions by following the many examples in the distributed server code (e.g., in the file `numbers.c'). Then follow the directions in the comment at the top of functions.c.
Alternatively, save a copy of the distributed file `extensions.c' and then edit the original to implement your new functions. The C function `register_extensions()' is already called at server startup to register whatever built-in functions are implemented in `extensions.c'. In future releases, you can simply replace the newly distributed `extensions.c' with your own.
NOTE that, in this release, I'm not making any guarantees about what interfaces within the server will remain stable. Thus, any code you add to the server may well be horribly broken by a future release. Your best bet for avoiding this cruel fate is to send that code to me and convince me to add it to the distribution; that way, I'll fix up your code for each new release.
Machines On Which Version 1.8.0 of LambdaMOO Was Tested
Hardware Operating System(s) Networking Options Compiler
-------- ------------------- ------------------ --------
Sun 4/SPARC SunOS 4.1.3, 5.5 SU, BT, BL, VT, VL GCC
SGI Iris IRIX 5.3 SU, BT, BL, VT, VL Vendor's
DEC Alpha DEC OSF/1 V3.2 SU, BT, BL, VL Vendor's
Intel x86 Linux 1.3.30 SU, BT, BL, VL GCC
Key to `Networking Options' codes:
Code NETWORK_PROTOCOL NETWORK_STYLE
---- ---------------- -------------
SU NP_SINGLE -----
BT NP_TCP NS_BSD
BL NP_LOCAL NS_BSD
VT NP_TCP NS_SYSV
VL NP_LOCAL NS_SYSV