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Burroughs KERMIT Kermit is written for the Burroughs in ALGOL. In general, as much intel- ligence as possible was put into Kermit-7800 to allow smooth communication with even the most minimal Kermit implementations. Packet lengths are typi- cally limited to 88 characters of data. Burroughs file specifications are of the form: (USERCODE)NAME1/NAME2/.../NAMEX with up to 12 names, each containing up to 17 characters. Most micros have file names of the form: namename.ext where namename may be up to 8 characters long and .ext is an optional name extension up to 3 characters long. For files transferred from the Burroughs, the filename sent is the name following the final slash (ie. NAMEX in the example above). If the name fol- lowing the slash is longer than 8 characters, a "." (period) will be inserted after the 8th character. If the name is longer than 11 characters, it will be truncated, eg.: Burroughs filename : sent as : (USERCODE)NAME1/.../LONGERTHAN11 longerth.an1 For files transferred to the Burroughs, if the filename contains any 'special characters' (as far as the Burroughs is concerned...) the filename on the Burroughs disk will be enclosed in quotes. Special characters include just about anything except alphanumeric characters and slashes. Refer to your WFL manual for a precise definition. Since the default character set on the Burroughs is EBCDIC, all text is appropriately translated to/from ASCII by Kermit. Files written by Kermit are translated to EBCDIC; files read by Kermit are translated to ASCII. There is no provision for overridding this, but since a full 8-bit translate table is used there is no loss of information. Kermit, by default, changes between fixed and variable length records. Normally, trailing blanks are stripped off of records transmitted by the Burroughs. Records received which are short have trailing blanks added to produce fixed length records, and long records are split into more than one fixed length record. These features are user con- trollable with the SET FILE command. Kermit-7800 must be run interactively and can be run only in remote mode. All file transfer is done over the job's controlling terminal line. What Bur- roughs presumes is that your terminal is really another computer running its own copy of Kermit. Kermit commands can be abbreviated using the minimum distinguishable string. For example, as a command 'SE' could be 'SET' or 'SEND' and will pro- duce an error; 'R' is sufficient for 'RECEIVE'. Abbreviations are context - 2 - sensitive. As a command, 'SE' is ambiguous; as an argument to 'STATUS' one can abbreviate 'SEND' with 'S'. One can check for ambiguous abbreviations by entering an abbreviation followed by '?' with no intervening space. Here are the Kermit-7800 commands: EXIT Exit from Kermit-7800, closing any open debugging log files. You may also stop Kermit-7800 in the midst of a transfer or during server operation by typing ?DS. HELP Gives a list of command verbs. Typing <command> ? will give options available for that command. QUIT A synonym for EXIT. RECEIVE Receive a file or group of files from other Kermit. SEND <filespec1> <filespec2> ... Send file(s) specified by <filespec1> <filespec2> ... to the other Kermit. This command may be used to send files to any Kermit, server or not. You should escape back to your local Kermit and give the RECEIVE command. If you don't do this fast enough, several "send-init" packets may arrive prematurely; don't worry, Kermit-7800 will keep sending them until it gets a response. SERVER Act as a Kermit Server with default options, or with whatever options have been established by previous SET commands. Note that all options remain as long as the server is running -- there is no way to change them without shutting down the server and restarting with new options. The server may be shut down from the local Kermit using a FINISH command, or by connecting back to the Burroughs and typing ?DS. A FINISH command halts the server without logging off CANDE. SET <parameter> <value> Set the specified parameter to the specified value. Some parameters have their own parameters. Possible settings: BINARY <value> On some systems, transmitting 8 bit data over a typical terminal line may result in corruption of the 8th bit. Kermit uses "binary quoting" to indicate to the receiver that a byte is to be stored with the high bit on. This method involves extra overhead, and should only be used when necessary to guarantee the integrity of the 8th bit of your data. ON Use "binary quoting" when transmitting bytes with the high bit on. - 3 - OFF Do not send any "binary quotes" when transmit- ting. The received value of the high bit is assumed to be arbitrary. This is the default. DEBUGGING <mode> When KERMIT is not transferring files successfully, it may be useful to inspect the messages that are sent between the two Kermits, or the internal state transitions. Several options are available. STATES Shows the packet number and type or internal state, for each packet. The packet types and states are: S Send Initiate R Receive Initiate F File Header D Data Z End of File B Break Transmission C Transfer Complete E Error A "Abort" Transmission T Timeout PACKETS Display the actual incoming and outgoing pack- ets. For a description of the packet format, see the Kermit Protocol Manual. LOG-FILE <filespec> Debugging display cannot be done to the screen since Kermit-7800 cannot run in local mode. This option allows the data to be logged to a file. If a SET DEBUG command has not previously been issued, this command will also force DEBUG- GING mode to STATES. SET DEBUGGING OFF will close the log file, as will the EXIT, BYE, and FINISH commands. (This option is currently not implemented completely. The log file is called KERMIT/LOG and may not be changed via the <filespec> but can be file-equated). OFF No debugging information will be displayed. If debugging was previously in effect, debugging is turned off and any debugging log file is closed. Debugging is OFF by default. The default <mode> for the SET DEBUG command, however, is STATES. DELAY <d> Specify the delay, in seconds, before sending the first send-init packet. This gives you time to "escape" back to your local Kermit and issue a RECEIVE command. Normal delay is 5 seconds. - 4 - FILE <parameter> <value> File parameters allow Kermit to control some attributes of the files being processed. FIXED applies only to files being read. The rest apply to files being written. BLOCK-SIZE <d> This option sets the number of UNITS per block for the receive file. Default BLOCK-SIZE is 420 (UNITS/block). Also see RECORD-SIZE and UNITS. EXPAND-TABS <value> Since not all software and hardware on the Bur- roughs can deal with tabs this option allows one to have tabs expanded into blanks. The tabs are fixed at 8 columns per tab, and not modifiable by Kermit. The default setting is ON, but set- ting RAW will turn this option OFF. ON Expand tabs into blanks. OFF Store the tab characters received into the output file. FIXED <value> Most Kermits deal with variable length records on their host machines. In order to be compati- ble with these systems, Kermit on the Burroughs converts files from fixed length to variable length records by stripping trailing blanks from each record before transmitting. This also helps reduce the number of bytes transmitted. ON Do not strip tailing blanks. Send all the data bytes. OFF Do not transmit trailing blanks. This is the default. RAW <parameter> The Burroughs tends to handle fixed-length records more easily than variable-length records. This option allows for receiving a file and packing it into records regardless of 'end-of-line' characters. ON Records are filled character-by- character. A new record is started only when the current record is full. OFF Records are filled character-by- character. A new record is started each time a NL (newline) character is received. This is the default. - 5 - RECORD-SIZE <d> The Burroughs uses fixed-length records, usu- ally. RECORD-SIZE sets the length in terms of UNITS, for the receive file. Default RECORD- SIZE is 15. UNITS <type> CHARACTERS -- The RECORD-SIZE and BLOCK-SIZE receive file attributes are measured in charac- ters (bytes). WORDS -- The RECORD-SIZE and BLOCK-SIZE receive file attributes are measured in Burroughs words (48 bits/word). This is the default. INCOMPLETE <disposition> Normally, when a file transfer cannot be completed (for instance, because the communication path suddenly breaks or becomes too noisy), the side receiving the file nor- mally "aborts" the operation -- that is, everything received so far is discarded. This command allows the user of Kermit-7800 to specify the disposition of par- tially received files upon abnormal termination of a file transfer: DISCARD Remove all traces of the partially received file from the Burroughs disk. KEEP Keep the file on disk, containing all the data that was transferred successfully up until the error occurred. This option may be useful when transferring very long files, when it is possi- ble to have the sending system start again at the place it was interrupted, e.g. by breaking the end of the file off with a text editor. This is the default. RETRY <parameter> <d> Set the maximum number of times Kermit-7800 will retry an operation before giving up and terminating the transfer. Parameters are INITIAL-CONNECTION and PACKETS. The normal values are 20 and 10, respectively, but can be set higher when the connection is noisy or other problems prevent a transfer from completing successfully. RECEIVE <parameter> <value> SEND <parameter> <value> These commands allow you to specify to the other Kermit what the packets it sends should look like, or to inform this Kermit what to expect. END-OF-LINE <d> The character the other Kermit should terminate its pack- ets with, CR (ASCII 15) by default. Kermit-7800 does - 6 - require the "line terminator" to be a CR. PACKET-LENGTH <d> The longest packet the other Kermit may send. Legal values are 10 to 94; the default is 94. PADDING <d>, PADCHAR <d> Inter-packet padding. The Burroughs does not need any padding. PAUSE <d> When receiving a file, pause the specified number of tenths of a second between receipt of a packet and sending the ACK or NAK. Default is no pause. QUOTE <char> The character the other Kermit should use for quoting con- trol characters, normally ASCII 43 ("#"). There should be no reason to change this. Permissible values are 41 ("!") to 176 ("~"), i.e. the ASCII characters in the printable range. START-OF-PACKET <d> The character the other Kermit will be using to start its packets. Normally ASCII 1 (SOH, CTRL-A). If the other Kermit is incapable of transmitting an ASCII 1, you may use this command to tell Kermit-7800 what character to expect. Permissible values are 1 (CTRL-A) to 37 (CTRL- Underscore). TIMEOUT <d> The minimum number of seconds after which the remote Ker- mit should time out when waiting for a packet. You may adjust this as necessary to accommodate various line speeds, or to compensate for slow systems. Legal values range from 1 to 94 seconds. The default is 5 seconds. SHOW [parameter] STATUS [parameter] Show the settings of parameters that can be affected by the SET com- mand, plus information about SEND or RECEIVE parameters. The param- eter (SEND or RECEIVE) will determine which set is displayed. The default is RECEIVE.