Kermit

[tyama501]

I have been using Kermit on DOS/Windows/Linux for Serial Port file transfers since there was pc-98 dos port of the original kermit.

I have been looking for some portable codes for elks and found this embbedable kermit.
https://github.com/KermitProject/ekermit

It seems that there is unixio.c and may be good to start.

[ghaerr]

Hello @tyama501,

Many years ago I was quite familiar with Kermit and ported it to many platforms. I would think it should be very straightforward to get it working on ELKS, hopefully using a termios port of unixio.c. If you'd like, it can be added to elkscmd/kermit for the standard distribution with a PR from you.

If you have questions about how setting up the serial port, elkscmd/miniterm.c should provide a pretty good example.

Thank you!

[tyama501]

Hello @ghaerr

Thank you.

BTW, I have noticed sercat is not included in fd1440-fat.img in the actions although it is marked as :1440c in the Application list.

https://github.com/ghaerr/elks/actions/runs/19917306624

I also build it my self and it is not included.
Any idea why this happen?

[ghaerr]

It looks like the Applications file used :1400c rather than :1440c. I'll push a fix on that now.

[tyama501]

I didn't notice that! Thank you :)

[tyama501]

Hello @ghaerr ,

I haven't tested yet and I haven't added termio for setting bit rate and others,
but I have made initial changes for ELKS and confirmed I can build with gcc-ia16.
tyama501/ekermit@8648cda

I needed to define NO_LP (it says no long packet) to reduce memory size.

I will test when I have another time.
Thank you.

[ghaerr]

the problem for the short binaries is just termination.

Can you explain what you mean by "short binaries" as well as "termination"? Thank you.

[tyama501]

I meant files less than 8192 bytes.
The termination means cannot detect c == k->r_eom /* Packet terminator */ which is CR,
to return.
I needed to send ^C^C^C from windows to the elks to stop and it is abnormal exit so the file is zero bytes.

[ghaerr]

You might want to check that ICRNL is not set in termios. The default is set, which incoming CRs to NLs.

[tyama501]

Actually, I haven't added the termios yet.

Now, I have made Hello.txt on windows with CR+LF and I have confirmed I can receive this file nicely :)

Thank you.

[tyama501]

Hello @ghaerr

I have added termios and set ~ICRNL.
tyama501/ekermit@45b8aef

It worked!
I could receive bootopts and cat on ELKS PC-98 from windows!

Thank you!

[parabyte]

I never used Kermit before, just never been required of me, so had to do a little research to get to grips with what you guys/girls doing here.

could it be possible that Documentation could be added to elks to explain to a end user how to send files using Kermit, from common machines.

in my case Debian current
Others will need documentation for Macos and other host machines they maybe running

[parabyte]

very good point! and been in this situation as a new *nix user in the past.

Hope my minimal instructions are okay on the ngircd readme

[tyama501]

Hello @parabyte and @ghaerr

I am still adding/debugging features but I will copy it to elkscmd/ once it is settled, so that more user can test and enhance it.
Maybe the following wiki can be updated as well.
https://github.com/ghaerr/elks/wiki/Networking:-File-Transfers

I think there is ckermit pakage in the debian although I haven't tested with that yet.

Thank you.

[tyama501]

I have made several changes including setting serial device. I also wrote simple README.
Almost ready to copy to elkscmd but I found one bug today that the serial device name is also tried to be sent as file when ekermit -s.
I will think to fix that.
Sending a file from PC-98 to windows worked if the default serial device is used.

https://github.com/tyama501/ekermit

Thank you.

[tyama501]

Hello @ghaerr ,

It is fixed.
tyama501/ekermit@179bc9f

I will copy these to elkscmd and make a first PR.

Thank you.

[tyama501]

#2554

[tyama501]

Hello,

I have made a small change to the serial section of the Wiki to mention E-Kermit.

https://github.com/ghaerr/elks/wiki/Networking:-File-Transfers

[tyama501]

Hello @ghaerr and @parabyte ,

I tried connecting with ckermit on Debian12.
Sending a file from ELKS to the ckermit Debian12 worked,
but somehow receiving from the ckermit didn't worked with errors.
I have used the following setting.

It says too many errors.

I would appreciate it if more user could test it.

Meanwhile, I will try to compile the ekermit with host gcc so that the users can use it on linux.

Thank you!

[ghaerr]

Hello @tyama501,

That change was from a suggestion from @Mellvik to fix a nonstandard (broken) iOS telnetd. I added it without much testing. Go ahead and delete line 1074 in lib/misc/linenoise.c and see if that fixes kermit. I would not think this should have an effect since sh should not be reading kermit-sent data. Please let me know. It seems that kermit requires LF line endings, correct? Were any other changes made to termios with ICRNL or INLCR?

it is receiving in debian but the file is not saved.

That sounds more like a file creat/open problem, especially if the Debian is receiving the file, not sending.

Thank you!

[tyama501]

Thank you.

I think Kermit uses CR.
I will test again when I have another time.

[tyama501]

It seem that the file is not saved if there is PATH in the filename.

I made a note on Readme.
#2592

I also fixed the hosek to accept USB device.

The ckermit still have trouble, but now
I could send/receive files with this hostek on Debian.

So I appreciate if Debian users test with this.

Thank you!

[tyama501]

Hello,

I finally found the c-kermit setting that can send file to the e-kermit on the ELKS.

c-kermit on Debian set the following,
set send packet-length 80
set window-size 1
set flow-control none
set carrier-watch off

The packet-length may related to
KermitProject/ckermit#19

The c-kermit can be installed to debian by apt.

Thank you!

[tyama501]

I have added link to this discussion on https://github.com/ghaerr/elks/wiki/Networking:-File-Transfers

[tyama501]

It seems that kermit project web page is still well maintained.

https://www.kermitproject.org/ek.html

https://www.kermitproject.org/ck90.html

[johnsonjh]

Hi guys, I have ucKermit which is a fork of old C-Kermit. I was able to get a version built with a little hacking that at least fired up in elksemu.

FULL:

uCKermit, 4G(178), 2023-MAY-19, ELKS 8086
Interactive mode.  Type '?' for help.
uCKermit>SHOW VERSION

  uCKermit, 4G(178), 2023-MAY-19, ELKS 8086
   Library, 4G(108)
  JSYS ICP, 4G(066)
   JSYS UI, 4G(128)
    TTY IO, 4G(096)
   File IO, 4G(097)
   Connect, 4G(057)
    Dialer, 4G(060)
    Script, 4G(039)

SMALL:

uCKermit>SHOW VERSION

  uCKermit, 4G(178), 2023-MAY-19, ELKS 8086
   Library, 4G(108)
  JSYS ICP, 4G(066)
   JSYS UI, 4G(128)
    TTY IO, 4G(096)
   File IO, 4G(097)

The documentation is at https://raw.githubusercontent.com/BAN-AI-Communications/uckermit/refs/heads/master/ckuker.doc but essentially it's C-Kermit 4.

I'm not sure if it will work at all, but maybe you can try it and see if it's worth adding a compilation target for ELKS. The minimal version is quite minimal, similar to e-kermit.

79424   kermit_elks_full
45360   kermit_elks_small
29296   kermit_elks_minimal

• kermit_elks_full.gz
• kermit_elks_minimal.gz
• kermit_elks_small.gz

I didn't test using the actual serial lines - but they could be made to work if it gets this far.

I'd try a transfer over the console/tty/telnet line (including the SERVER mode) which should work.

I don't have a real hardware ELKS system to test on right now, but maybe one of you can give it a try?

[johnsonjh]

@tyama501 I should mention that in the small build of uckermit you have a maximum packet length of 90, but you should be able to go up to to 1200 in the full version:

Line: /dev/tty, speed: -1, mode: remote, modem-dialer: direct
Bits: 8, parity: none, duplex: full, flow: XON/XOFF, handshake: none
Terminal emulation: 7 bits, Initialization file: .uckermrc

Protocol Parameters:   Send    Receive    (* = override)
 Timeout:               10        9        Server timeout:  40
 Padding:                0        0        Block Check:      1
 Pad Character:          0        0        Delay:            5
 Packet Start:           1        1        Max Retries:     12
 Packet End:            13       13
 Packet Length:       1200*    1200 (94)
 Length Limit:        1200     1200

File parameters:               Attributes:       on
 File Names:    converted      Debugging Log:    none
 Transfer Mode: binary         Packet Log:       none
 Overwrite:     off            Session Log:      none
 Info Display:  on             Transaction Log:  none

File Byte Size: 8, Incomplete File Disposition: discard

[ghaerr]

you should be able to go up to to 1200 in the full version

Keep in mind that the default serial input queue ring buffer is only 1024 bytes, set by RSINQ_SIZE in include/linuxmt/ntty.h. Using 1024 or less for the full packet size, input can be received at a very high baud rate without the application having to run before losing input data.

I'd try a transfer over the console/tty/telnet line

Agreed, a serial tty line should work well with packet size < 1024 bytes. However, non-serial TTYs and PTYs used for networking have a queue size of only 80 bytes (INQ_SIZE and PTYINQ_SIZE) , although of course TCP might help with flow control (although that's also somewhat limited in ELKS).

[johnsonjh]

Hey @tyama501 did you ever have a moment to try using the μCKermit binaries from #2495 (comment) on a real ELKS system?

[johnsonjh]

Yes, you would "set line" first. Then "set speed", "set parity", "set flow-control", etc.

[tyama501]

Hello @johnsonjh

I have tried kermit_elks_full on PC-98. It seems that it says Can't condition line for send/receive.

It also have some warning when opening line. Do you think this warning is critical?

Here is the configuration I have set.

Can't condition line for send. Receive also gets same message.

I could transfer a file with my ekermit, so I think the hardware is alive.

Thank you.

[johnsonjh]

@tyama501

Thanks for checking! Since I don’t have ELKS on anything with a serial port I couldn’t test myself. Perhaps I’ll need to setup proper full system emulation on 86Box or similar.

Those warnings are not critical, it uses a locking mechanism to prevent multiple users or processes from trying to access the same serial port.

The “Can’t condition line” message means that μCKermit failed to set the flow control, speed, or parity itself.

If you are able set these yourself correctly using stty or similar, and ensure the μCKermit settings match what you set, I’m providing an updated “full” build here - it just removes that check. :)

Attached: kermit_elks_full.gz

If this doesn't work for you, I'll probably have to setup emulation that has serial support to ensure a proper port.

I should also note the reason you see the command you just type echoed back is because μCKermit does some hackery to give context sensitive help (like C-Kermit on UNIX currently does, where you can press ? to see available options) and that's not working on ELKS just yet. That defect though is purely cosmetic.

[tyama501]

Thank you. I will try that later.

[tyama501]

Hello @johnsonjh

I have tried the updated kermit_elks_full after setting speed with stty, but it seems that I gets the same result saying "Can't condition line".

Looking at the Ckermit on debian connected, it seems there is some response but there is no packet coming.

Thank you.

[johnsonjh]

Thanks for trying it. Rather than waste your time further I will get a real emulation setup where I can run ELKS with a serial port and I’ll get it working that way.

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On Sat, Jun 6, 2026, at 12:56 PM, Takahiro Yamada wrote: Hello @johnsonjh <https://github.com/johnsonjh> I have tried the updated kermit_elks_full after setting speed with stty, but it seems that I gets the same result saying "Can't condition line". Looking at the Ckermit on debian connected, it seems there is some response but there is no packet coming. Thank you. — Reply to this email directly, view it on GitHub <#2495?email_source=notifications&email_token=AOWGFJQWNZELCUPBV74HGXT46RELBA5CNFSNUABIM5UWIORPF5TWS5BNNB2WEL2ENFZWG5LTONUW63SDN5WW2ZLOOQXTCNZSGA2DAOJQUZZGKYLTN5XKO3LFNZ2GS33OUVSXMZLOOSWGM33PORSXEX3DNRUWG2Y#discussioncomment-17204090>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AOWGFJUDOWD3NX7WN6FQG4T46RELBAVCNFSM6AAAAACN5CJYS2VHI2DSMVQWIX3LMV43URDJONRXK43TNFXW4Q3PNVWWK3TUHMYTOMRQGQYDSMA>. Triage notifications, keep track of coding agent tasks and review pull requests on the go with GitHub Mobile for iOS <https://github.com/notifications/mobile/ios/AOWGFJQH7OJSMGC3N3Q2JX346RELBA5CNFSNUABIM5UWIORPF5TWS5BNNB2WEL2ENFZWG5LTONUW63SDN5WW2ZLOOQXTCNZSGA2DAOJQUZZGKYLTN5XKO3LFNZ2GS33OUVSXMZLOOSVGM33PORSXEX3JN5ZQ> and Android <https://github.com/notifications/mobile/android/AOWGFJS6R6CS7A4YCEOZTUT46RELBA5CNFSNUABIM5UWIORPF5TWS5BNNB2WEL2ENFZWG5LTONUW63SDN5WW2ZLOOQXTCNZSGA2DAOJQUZZGKYLTN5XKO3LFNZ2GS33OUVSXMZLOOSXGM33PORSXEX3BNZSHE33JMQ>. Download it today! You are receiving this because you were mentioned.Message ID: ***@***.***>