Hello Jorge,

Tuesday, January 14, 2003, 6:02:14 AM CET, you wrote:

JAS> These terminals are now supposed to be able to have Bar Code Readers
JAS> attached to the serial ports of the machines !!

JAS> If I cannot do this with LTSP I am going to be forced to GO Full Linux
JAS> on the Desktop machines on the floor or worse Yet Install M$ on them !!!
JAS> How can I accomplish this ? I have been reading about mice and serially
JAS> attached "Touch devices" & Printers but there is no mention anywhere of
JAS> any other serially attached devices. 

I'm sure it is possible. Mostly, these bar code scanner devices will
just send the bytes they read in (and a start "*" and stop "#" or so,
for some models ?)... So they don't need bidirectional communications
which eases the problem a lot.
You could inform yourself about "mserver" (sometimes referred to as
"modemserver") which usually has the task to export a serial port via
network, so that other machines (M$Win as well as Linux) can mount
that port as "local".

You will run into a problem probably, that is: When there are three
terminals with a barcode scanner each, and users aaron, bob and carmen
scanning parts, how will the server know (because that's where the
programs are executed if they are not local_apps) which serial port to
connect to which user?

If it was my project, I probably would try to run it like this (rough
thoughts only :-)
Create /var/barcode, and one fifo-endpoint with the name of each user
that uses the scanner (Permissions as restrictive as possible, best
0400). Program a small server app that accepts udp packages from only
the IP addresses of terminals (security, be sure noone can hang into
your net then it's at least safer than the keyboard-barcode-method).
On each terminal, run a daemon that sends any serial input to that
daemon. Then, get your server's window manager write every login to a
file (so that the daemon can lookup where a user is logged in; works
only if no user is logged in twice! activate 'autologout'?) and for
every incoming package, let the daemon look up what user it comes from
and write to that fifo.

JAS> I am guessing that I am touching on a whole new subject here but I hope
JAS> I am wrong and somebody out there has been able to do this ...
JAS> I am guessing this would be along the lines of ltsp_nbd ... 
JAS> (currently used for Terminal floppy access)

nbd stands for "network block devices". Serial ports are usually
"character devices".

JAS> Thanks a Bunch.
JAS> Adrian Salaices.
JAS> Applications Manager/DBA
JAS> Dallas Airmotive. 
JAS> mailto:[EMAIL PROTECTED] 

Just some cents from here. If I did not have so lots of 'open' projects
on my todo lists, phew! I liked to scribble down something :-)

Best regards,
 Anselm                            mailto:[EMAIL PROTECTED]

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