1
2 09/21/87 kermit
3 Known errors in the current release of kermit.
4 # Associated TR's
5 Description
6
7 19 phx20214
8 Running kermit over a network block transfer is not possible at low
9 baud rates will cause kermit to become confused. kermit_pad_ assumes
10 that it is operating in block transfer mode, so that if it receives any
11 characters, it will be a whole block or multiples of blocks. It
12 completely drops packet fragments thus making network ARPANET
13 transfers at low baud rates impossible. This is because if the user is
14 sending a file at 300 baud, it will send a few characters at a time.
15 kermit_pad_ will wake up, notice that it has a packet fragment and
16 discard it.
17
18 Proposed solution:
19
20 Modify receive packet internal procedure within kermit_pad_ to retain
21 packet fragments and assemble them as they come.
22
23 18 phx20954
24 Optimizer bug in kermit.
25
26 Proposed solution:
27
28 Packet_fix and packet_type should be added in kermit_pad_ to get around
29 optimizer bug.
30
31 17 phx20955 phx20846
32 kermit is unable to handle multisegment files. Approximately one out
33 of 4 or 5 million byte would be missing when transferring MSF files.
34
35 Proposed solution:
36
37 Add support for MSF files : change substr parameters, detect the
38 improperly decoded packets and retry them, handle the lost packets
39 carefully, and use vfile for debug to allow for MSF trace.
40
41 16 phx20953,phx20952
42 The currect kermit is unable to handle extended packet header and
43 unable to communicate with nos/ve kermit due to extraneous data being
44 transmitted by nos/ve.
45
46 Proposed solution:
47
48 Add support of extended packet header, enhance packet handling, extend
49 maximum packet size from 96 to 1500 characters, and add modes for
50 capabilities, window size and maximum extened packet length.
51
52 15 phx20956
53 Difficulties in representing characters, such as CR and NL in the
54 source programs.
55
56 Proposed solution:
57
58 The definition of CR and NL should be moved to an include file, and
59 should be coded as bit strings with overlays.
60
61 14 phx20948
62 Incorrect parity value "off" is found in kermit_mode_mgr_. The 5 valid
63 parity values are "none", "space", "mark", "even" and "odd".
64
65 13 phx20103
66 kermit will sometimes echo packets while in server mode, and mistakes
67 timeouts while idling as legitimate packets. Upon entering server
68 mode, kermit will wait for 5 seconds before setting the line
69 characteristic for data transfer. It also resets the line
70 characteristics between file transfer. Any packets received at this
71 time will be echoed to the caller as invalid packets.
72
73 In addition, kermit will process timeouts while idling as legitimate
74 packets when waiting for packet zero 0. This causes it to send error
75 packets with the Unimplemented command message. This causes difficulty
76 starting loading after a pause.
77
78 Proposed solution:
79
80 kermit_info.incl.pl1:
81 Add server and transfer_modes_set indicators in the
82 "kermit_comm_info" structure.
83
84 kermit.pl1:
85 Do not set "server" and "transfer_modes_set" flags unless it is in
86 the server mode.
87
88 kermit_comm_mgr_.pl1:
89 Use "transfer_modes_set" flag so that initial line modes cannot be
90 lost.
91
92 kermit_server_request_.pl1:
93 Set the "server" flag properly according to the mode. Delete the 5
94 second waiting and set file transfer mode immediately.
95
96 kermit_server_.pl1:
97 Idle until a valid packet is received regardless of the packet
98 number. Remove all reset_line_modes except before logout.
99
100 12 phx20598
101 Some systems does not support the repeat character. When requesting
102 files from is via get filename the requested filename sent to the
103 remote uses the repeat_char "~" to represent the trailing blanks. The
104 server rejects this as an illegal filename. Using rtrim on the
105 filename helps, but still a filename like "aaaaaa" would be sent as
106 "~a". Since the Receive_init_packet can be sent before protocol has
107 been negotiated it should never be encoded or decoded before
108 determining whether the server kermit will honour its encoding.
109
110 Proposed solution:
111 kermit_remote_requests_.pl1:
112 Use rtrim to remove trailing blanks of the filename when sending
113 file to the remote.
114
115 kermit_pad_.pl1:
116 Do not encode or decode Receive_init_packets before determining
117 whether the server kermit will honour its encoding.
118
119 11 phx20633
120 kermit_comm_mgr_ does not set "^breakall" mode when setting "blk_xfer".
121 This means that wakeups may not be received when data arrives.
122
123 Proposed solution: The "^breakall" mode should be added to the list of
124 Constant_modes. If a user has "breakall" enable on the io switch used
125 by kermit wakeups don't arrive. When "breakall" and "blk_xfer" modes
126 are both set problems may arise. So if "blk_xfer" mode is used then
127 "^breakall" should be set else switch "iox_$user_io" should be used.
128
129 The affected module:
130 kermit_comm_mgr_.pl1
131 Add "^breakall" indicators. Set "^breakall" and "blk_xfer" modes
132 together to avoid further problems.
133
134 8 phx19739
135 Multics kermit does not use the packet-length and control-quoting
136 character provided by the local kermit correctly. When sending data
137 from Multics kermit to a local kermit Multics kermit does not use the
138 "receive packet length" that is provided by the local kermit. As a
139 result the same packet length is used regardless of whether
140 Multics-kermit is sending or receiving.
141
142 A similar problem exists for the character used to quote control
143 characters. If the control quoting characters for the two systems
144 differ Multics will use the local kermit's control quoting character
145 for both output and input. It should use the local kermit's control
146 quoting character for input only.
147
148 6 phx19091
149 When a file is transmitted from a Mac to Multics a "^@" is added to the
150 end of the filename. It is the Mac Kermit that adds the "^@"; thus it
151 is the culprit not Multics Kermit.