Date: Thu, 04 Oct 84 14:51:26 EDT   
From: Edgar B. Butt <BUTT@UMD2.ARPA>
To: sy.fdc@cu20b
Subject: Kermit in Pascal for the Sperry 1100

Here is a Kermit implementation for the Sperry 1100 systems written 
in Pascal.  It has been run successfully here at the University of Maryland,
College Park, and at SUNY, Albany.  Please add it to your selection 
of Kermits.  I would appreciate feedback from anyone who tries it.  

The first page of code consists of comments explaining how to   
use and generate Kermit1100.

Hop someone finds it useful,

Edgar Butt (Butt@umd2.arpa) 
Computer Science Center 
University of Maryland  
College Park, Maryland 20742
(301) 454-2946  

The source for Kermit1100 version 2.0 begins on the next line.  
{Kermit1100 - see first executable line in main block for version   

   KERMIT1100 is yet another Kermit written to run on the Sperry (Univac)   
   1100 series of computers.  It is written in Pascal to be compiled on 
   the NOSC Pascal Compiler, version 2.2 or later.  This compiler is
   available from the Computer Science Center of the University of  
   Maryland, College Park, for a nominal service charge.

   Kermit aficianodos may notice that the structure of this version 
   differs from other versions in that packets are read and sequence
   checked in the main program loop and are then dispatched to the  
   proper input or output state with a single case statement.   
   This structure has allowed the various state processes to be 
   relatively uncluttered.  While doing this implementation I   
   discovered that NAK's are like tadpole tails.  They seem like
   a neat idea at first, but as the frog emerges, they serve no 
   useful purpose.  Likewise, I have been unable to find a case 
   in which NAK's are necessary.  Sending an ACK for the last   
   good packet received is just as good.  If I'm wrong, I am sure   
   that some swamp dweller out there will let me know.  
   (Not to worry, I handle incoming NAK's even though they are not  
   necessary.)  

   By way of a quick synopsys of features, this version of Kermit has:  

      Simple server mode - processes S and R packets
      8-bit quoting (Turned on by Q-option) 
      Repeat count prefixes 
      Error packet generation and processing

   Kermit 1100 is called as a processor with the following control card:

      @Q*F.KERMIT,OPTIONS 1100SPEC,REMOTESPEC   

      Q*F. is the file in which the processor resides.  
      1100SPEC is the 1100 file or element on which Kermit will operate.
      REMOTESPEC is the file name sent to the remote Kermit(a fib of sorts) 
      OPTIONS:  
         B - big buffers.  Kermit1100 normally tells the remote Kermit to send
             packets that will fit in 84 characters.  B-option causes it to
             request the maximum size Kermit packets (which ain't as big as you
             might wish)  Make sure that your communications hardware and
             software will let the long packets get through.
         C - assume for sending or receiving that records are to be separated
             by CR instead of CR-LF 
         L - log in the element KERMITLOG.MDSSS all file reads and writes and
             all communication sends and receives. MDSSS is the month, day and
             seconds/4 encoded base 32 (0,...,9,A,...,V). If a catalogued file
             'KERMITLOG' is assignable, it is used.  Otherwise a temporary file
             is created.
         Q - allow eight-bit quoting for sending or receiving.  If the file 
             being sent or received has 8-bit data and if the remote kermit 
             is capable of 8-bit quoting, then all 8-bits of data can be
             sent or received.  
         R - expect to receive data.  Put the data in 1100SPEC if specified 
             or in the file or element name sent from the remote Kermit.  No
             transformation on the incoming name is done at present so it   
             had better be good.
         S - send 1100SPEC to the remote Kermit.  If REMOTESPEC is specified,
             put it in the file header packet.  Otherwise put 1100SPEC in the
             packet.
         T - test mode.  Send (actually print on a terminal) packets as if  
             an S-option had been specified without reading ACK's.
         W - If the S-option is used, wait 30 seconds before starting to send

Kermit1100 tries not to exit until an EOF is received in order to process   
multiple requests from the remote Kermit.   

   Happy hopping,   

      Edgar Butt  (BUTT@UMD2.ARPA)  
      Computer Science Center   
      University of Maryland
      College Park, Maryland 20742  
      Phone (301) 454-2946  

}