Added public files
Roughly added all public files. Probably missed some, though.
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+CONCEPT
+ imp
+
+LAST UPDATED
+ Deepthought, 10-Nov-92
+ Pepel, 18-Nov-93
+
+DESRIPTION
+ This document describes IMP, the intermud message protocol,
+ also known as Intermud-1.
+
+ Imp messages are exchanged between muds using UDP
+ (unreliable datagram protocol) packets. Each mud provides
+ a connection endpoint which is given by the ip host address
+ and the UDP port number. Muds may then send messages to
+ this port by using the efun send_udp(). The applied function
+ receive_udp will be called by the driver in the master
+ object if a imp message arrives at the mud's UDP port.
+
+ Imp message packets have the following format:
+
+ password@objectname@functionname[[@argument]...]
+
+ <password> is the connection password to verify incoming
+ imp packets. It is encoded using crypt(E) and compared to
+ the stored password. Each mud participating in the imp
+ network has a secret password which is encoded by the
+ admin and distributed to remote muds with which the mud
+ should have direct connection. Encryted passwords may also
+ propagated to other muds over already secure channels.
+
+ <objectname> is a logical name which is not to be confused
+ with mudlib object filenames. It is used by receive_msg in
+ the master object to route the message to another object by
+ associating the logical object name with a real mudlib file
+ name. A good idea would be to reserve a special directory
+ for imp objects, e.g. /secure/net/<objectname>.
+
+ <functionname> is the function which is called by the master
+ object in the object described by <objectname>.
+
+ <argument> are additional arguments which are handed to the
+ function <functionname>. The exact definition of functions
+ and arguments are left to the imp applications.
+
+AUTHOR
+ originally Deepthought
+
+NOTE
+ The above is only particularly correct nowadays. Recently a
+ package name ``inetd'' was published, that is based on the IMP
+ mechanism in the driver (send_udp() and receive_udp()), but
+ it uses a different message format. That package seems to
+ enjoy much publicity and is installed in a number of muds. For
+ details look into the inetd description.
+
+ An other method of inter mud connection is the Mudlink
+ package, which uses a normal user connection that is connected
+ to a special user object, and an auxiliary process that does
+ the connection to other muds.
+
+SEE ALSO
+ send_udp(E), receive_udp(M), intermud(C)