09/21/87 kermit Known errors in the current release of kermit. # Associated TR's Description 19 phx20214 Running kermit over a network block transfer is not possible at low baud rates will cause kermit to become confused. kermit_pad_ assumes that it is operating in block transfer mode, so that if it receives any characters, it will be a whole block or multiples of blocks. It completely drops packet fragments thus making network (ARPANET) transfers at low baud rates impossible. This is because if the user is sending a file at 300 baud, it will send a few characters at a time. kermit_pad_ will wake up, notice that it has a packet fragment and discard it. Proposed solution: Modify receive packet internal procedure within kermit_pad_ to retain packet fragments and assemble them as they come. 18 phx20954 Optimizer bug in kermit. Proposed solution: Packet_fix and packet_type should be added in kermit_pad_ to get around optimizer bug. 17 phx20955 phx20846 kermit is unable to handle multisegment files. Approximately one out of 4 or 5 million byte would be missing when transferring MSF files. Proposed solution: Add support for MSF files : change substr parameters, detect the improperly decoded packets and retry them, handle the lost packets carefully, and use vfile for debug to allow for MSF trace. 16 phx20953,phx20952 The currect kermit is unable to handle extended packet header and unable to communicate with nos/ve kermit due to extraneous data being transmitted by nos/ve. Proposed solution: Add support of extended packet header, enhance packet handling, extend maximum packet size from 96 to 1500 characters, and add modes for capabilities, window size and maximum extened packet length. 15 phx20956 Difficulties in representing characters, such as CR and NL in the source programs. Proposed solution: The definition of CR and NL should be moved to an include file, and should be coded as bit strings with overlays. 14 phx20948 Incorrect parity value "off" is found in kermit_mode_mgr_. The 5 valid parity values are "none", "space", "mark", "even" and "odd". 13 phx20103 kermit will sometimes echo packets while in server mode, and mistakes timeouts while idling as legitimate packets. Upon entering server mode, kermit will wait for 5 seconds before setting the line characteristic for data transfer. It also resets the line characteristics between file transfer. Any packets received at this time will be echoed to the caller as invalid packets. In addition, kermit will process timeouts while idling as legitimate packets when waiting for packet zero (0). This causes it to send error packets with the Unimplemented command message. This causes difficulty starting loading after a pause. Proposed solution: kermit_info.incl.pl1: Add server and transfer_modes_set indicators in the "kermit_comm_info" structure. kermit.pl1: Do not set "server" and "transfer_modes_set" flags unless it is in the server mode. kermit_comm_mgr_.pl1: Use "transfer_modes_set" flag so that initial line modes cannot be lost. kermit_server_request_.pl1: Set the "server" flag properly according to the mode. Delete the 5 second waiting and set file transfer mode immediately. kermit_server_.pl1: Idle until a valid packet is received regardless of the packet number. Remove all reset_line_modes except before logout. 12 phx20598 Some systems does not support the repeat character. When requesting files from is (via get filename) the requested filename sent to the remote uses the repeat_char "~" to represent the trailing blanks. The server rejects this as an illegal filename. Using rtrim on the filename helps, but still a filename like "aaaaaa" would be sent as "~(a". Since the Receive_init_packet can be sent before protocol has been negotiated, it should never be encoded or decoded before determining whether the server kermit will honour its encoding. Proposed solution: kermit_remote_requests_.pl1: Use rtrim to remove trailing blanks of the filename when sending file to the remote. kermit_pad_.pl1: Do not encode or decode Receive_init_packets before determining whether the server kermit will honour its encoding. 11 phx20633 kermit_comm_mgr_ does not set "^breakall" mode when setting "blk_xfer". This means that wakeups may not be received when data arrives. Proposed solution: The "^breakall" mode should be added to the list of Constant_modes. If a user has "breakall" enable on the io switch used by kermit, wakeups don't arrive. When "breakall" and "blk_xfer" modes are both set, problems may arise. So, if "blk_xfer" mode is used, then "^breakall" should be set, else switch "iox_$user_io" should be used. The affected module: kermit_comm_mgr_.pl1 Add "^breakall" indicators. Set "^breakall" and "blk_xfer" modes together to avoid further problems. 8 phx19739 Multics kermit does not use the packet-length and control-quoting character provided by the local kermit correctly. When sending data from Multics kermit to a local kermit, Multics kermit does not use the "receive packet length" that is provided by the local kermit. As a result, the same packet length is used, regardless of whether Multics-kermit is sending or receiving. A similar problem exists for the character used to quote control characters. If the control quoting characters for the two systems differ, Multics will use the local kermit's control quoting character for both output and input. It should use the local kermit's control quoting character for input only. 6 phx19091 When a file is transmitted from a Mac to Multics, a "" is added to the end of the filename. It is the Mac Kermit that adds the ""; thus, it is the culprit, not Multics Kermit. ----------------------------------------------------------- Historical Background This edition of the Multics software materials and documentation is provided and donated to Massachusetts Institute of Technology by Group BULL including BULL HN Information Systems Inc. as a contribution to computer science knowledge. This donation is made also to give evidence of the common contributions of Massachusetts Institute of Technology, Bell Laboratories, General Electric, Honeywell Information Systems Inc., Honeywell BULL Inc., Groupe BULL and BULL HN Information Systems Inc. to the development of this operating system. Multics development was initiated by Massachusetts Institute of Technology Project MAC (1963-1970), renamed the MIT Laboratory for Computer Science and Artificial Intelligence in the mid 1970s, under the leadership of Professor Fernando Jose Corbato. Users consider that Multics provided the best software architecture for managing computer hardware properly and for executing programs. Many subsequent operating systems incorporated Multics principles. Multics was distributed in 1975 to 2000 by Group Bull in Europe , and in the U.S. by Bull HN Information Systems Inc., as successor in interest by change in name only to Honeywell Bull Inc. and Honeywell Information Systems Inc. . ----------------------------------------------------------- Permission to use, copy, modify, and distribute these programs and their documentation for any purpose and without fee is hereby granted,provided that the below copyright notice and historical background appear in all copies and that both the copyright notice and historical background and this permission notice appear in supporting documentation, and that the names of MIT, HIS, BULL or BULL HN not be used in advertising or publicity pertaining to distribution of the programs without specific prior written permission. Copyright 1972 by Massachusetts Institute of Technology and Honeywell Information Systems Inc. Copyright 2006 by BULL HN Information Systems Inc. Copyright 2006 by Bull SAS All Rights Reserved