Very Computer

System: linux 0.99pl12, running /bin/getty 9600 /dev/ttyS0 (COM1)

I suspect a problem with switching to noecho mode on the serial
line because a userid with no password required does indeed result
in a shell being spawned.

Any trouble-shooting suggestions from you serial gurus?

Thanks!

Shih-Ping Chan

My solution was to use /dev/cua0 instead of /dev/ttyS0.

Is it possible that the tty/cua locking code has problems with some wierd
serial port types?

Alan

--
--- Alan Storey          | "When love and skill work together, |

--- (not my employer)    |                       -- C. Reade   |  

   >but I do not get the Password: prompt. If I do a ps aux
   >I see "login userid" running as if it were waiting for me to
   >type in a password. But I nothing happens on the terminal side.
   >
   >System: linux 0.99pl12, running /bin/getty 9600 /dev/ttyS0 (COM1)
   >
   >I suspect a problem with switching to noecho mode on the serial
   >line because a userid with no password required does indeed result
   >in a shell being spawned.
   >
   >Any trouble-shooting suggestions from you serial gurus?

Yeah, that looks like when login is which to noecho mode, it is also
managing to clear the CLOCAL flag --- this causes the serial driver to
hang on open waiting for the DTR line to go high.  I suspect it's a
problem with your /bin/login binary.  If you don't need to prompt for a
password, then it doesn't much with the termio flags, so it doesn't
clear the CLOCAL flag.

   While I'm not a serial guru I have run into the same problem on my
   AST Laptop.  I believe that certain serial hardware has problems in
   this area.  I have run the EXACT same setup on my Compaq Deskpro and
   do not have the problem at all.

   My solution was to use /dev/cua0 instead of /dev/ttyS0.

You have the same configuration setup --- are you sure you have the same
getty and login binaries?  This really smells like a problem with some
rogue program modifying the CLOCAL termios flag.  To test this, try doing a
"stty everything" on the serial line from another tty, and see if the
CLOCAL flag is properly set during the entire login sequence.

                                                        - Ted

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|>Newsgroups: comp.os.linux.help
|>I am trying to attach a PC with Kermit as a terminal via
|>null modem cable to a serial port. I do get the login: prompt
|>and I can type my userid[return]
|>but I do not get the Password: prompt. If I do a ps aux
|>I see "login userid" running as if it were waiting for me to
|>type in a password. But I nothing happens on the terminal side.
|>
|>System: linux 0.99pl12, running /bin/getty 9600 /dev/ttyS0 (COM1)
|>
|>I suspect a problem with switching to noecho mode on the serial
|>line because a userid with no password required does indeed result
|>in a shell being spawned.
|>
|>Any trouble-shooting suggestions from you serial gurus?
Me=no guru :)
Try /dev/cua0 or cua1  in the place of/dev/ttyS0
Don't know if this is the way to do it, but it works for me anyway.. :)

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