I want to transfer a big file of 70MB to a virtual machine running an ancient unix(at&t 2.1 ),no cdrom driver,no ufs disk(linux give me error when i try to mount systemV ufs,with ufs 43bsd ok),no floppy(no 70MB floppy exist..) So i choose minicom+kermit On at&t side i give

kermit -g file.tar

On linux side i open minicom


choose kermit,choose file.tar and wow...nothing happen. On at&t serial screen i see

/usr/local/bin/kermit -g file.tar                                                           
Return to your local Kermit and give a SERVER command.                                                                  

KERMIT READY TO GET...                                                                                                  
3 EToo many retries_N"U1@            

Any solution?

  • As it just happens... I was working on this last weekend :-). pbs.twimg.com/media/CVP4hp1W4AAbzGY.png. Will get back to you on this... – Criveti Mihai Dec 2 '15 at 20:46
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    I'd suggest kermit -O on the AT&T side, and then kermit on the local side (set line /dev/tty..., set baud 19200, set carrier-watch off, set flow-control none, send file.tar) – roaima Dec 2 '15 at 22:28
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    Can you check, in minicom, that both hw and sw flow control are off? – Mark Plotnick Dec 2 '15 at 23:49
  • Does the VM have a network interface? does it have NFS client software? if so, you could create an NFS export somewhere (on the VM's host machine, perhaps) and mount it on the VM. Even without NFS, it might have an ftp client or possibly even a http client you could use to download the file over the network. – cas Dec 3 '15 at 0:03
  • AT&T unix no tcp drivers avaliable anywhere – elbarna Dec 3 '15 at 14:07

I've used qemu + QEmu Monitor to mount floppies and read the raw data with dd.

Write your file one floppy at a time with dd or split:

Note: You may need to split into volumes of 1474560 (that's what /dev/rdsk/f03ht seems to be).

You can optionally try to use compress as well.

# Archive the files you wish to send using `tar` (supported on SYSV). 
$ ls -la test.tar
----------+ 1 cmihai None 5901312 Dec  2 20:55 test.tar

# Split into 1.44MB volumes
$ split -b 1478656 test.tar test_floppy_

$ ls -la test_floppy*
-rw-r--r--+ 1 cmihai None 1478656 Dec  2 21:10 test_floppy_aa
-rw-r--r--+ 1 cmihai None 1478656 Dec  2 21:10 test_floppy_ab
-rw-r--r--+ 1 cmihai None 1478656 Dec  2 21:10 test_floppy_ac
-rw-r--r--+ 1 cmihai None 1465344 Dec  2 21:10 test_floppy_ad

Mount the floppy in qemu.

Press Ctrl + Alt + 2 in qemu to use the qemu monitor.

change floppy0 test_floppy_aa
info block

Go back your terminal by pressing Ctrl + Alt + 1

Note: We should probably read off the raw device /dev/rdsk/f03ht not the block device... to test.

dd if=/dev/dsk/f03ht of=test_floppy_aa
dd if=/dev/dsk/f03ht of=test_floppy_ab


cat a b c | tar -tvt test_floppy_* # test..
cat a b c | tar -xvt test_floppy_*

Other ideas

  • qemu-system-i386 -hda sysv.img -hdb test.tar and read with dd from /dev/rdsk/1s1 (I guess... 0s0 is the root disk). You can also try to `fdisk /dev/rdsk/1s1'.
  • Append to the end of the existing disk image, and read with dd :D. (insane...)
  • May need to use /dev/fd or /dev/rdsk devices...
  • Converting from RAW to VMDK (usable by VMware and VirtualBox): qemu-img convert -O vmdk sysv.img sysv.vmdk. Now we can try to see if VMware or VirtualBox NIC drivers are supported...
  • Will try kermit / tip / cu as soon as I find the floppy that contains them and the /dev/ I need to use...


  • tar can read directly from /dev/dsk/f03ht. Ex: tar -tvf /dev/dsk/f03ht. Should probably try to create a multi volume floppy and forget about the dd part... WIP :-).
  • 1
    70MB of data via floppy? Seriously? – roaima Dec 2 '15 at 22:29
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    Going to be faster than kermit / minicom... that's for sure :-). Besides, this thing gets installed from 43 floppies (or so..). Not much else you can do if you don't have a filesystem driver, a cdrom device or a network stack... – Criveti Mihai Dec 2 '15 at 22:31
  • Advantage of kermit/minicom is that you can walk away from it, though. Two minutes per floppy... assume two (or three) floppies on the go... around a couple of hours of swapping. Yes, ok, I suppose it's not too bad. – roaima Dec 2 '15 at 22:34
  • Cu is a good idea. OP will only need cu on one side, and it's easy to install from linux distro repositories. Would need uuencode on the Linux side and uudecode on the SVR2 side. – Mark Plotnick Dec 3 '15 at 9:50

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