In article <BtyI3r.HEn@watserv1.uwaterloo.ca> hesse@watserv1.uwaterloo.ca (BJ Cameron - DCS) writes:
>
>Gee Brad, you just get back from vacation? :) I posted this back in July. I guess I should have posted a followup with the answer received from Rich Coe via mail.
>He suggested:
>
> /* push the posix line discipline */
>ioctl(fd, TXADDCD, "posix");
>ioctl(fd, TCSBRK, 0);
> /* pop the posix line discipline */
>ioctl(fd, TXDELCD, "posix");
>
>>>>Any ideas?
>>
>> When using a serial printer, you are normally talking to the serial printer
>> line discipline...not the posix line discipline. The TCSBRK and TCSBREAK
>> support are in the posix line discipline. You're outta luck.
>
>I tried the above and it works fine; it allows sending a break signal over a
>serial line defined as /dev/lp1. Hope this helps anyone else trying to print
>through a modem or other communication device.
>
>Bri
July, eh ? That may be old for a newsgroup posting, but it can be young for
a tty PMR ! Rich's suggestion is technically feasible, but I'm not sure
how practical it is. If you are talking to this printer strictly under
program contol, this would be fine. If the printer is part of the spooling
subsystem (backend, qdeamon, etc.) you might be asking for trouble...just
imagine what would happen if the backend started spewing serial discipline
specific ioctls (or read/write semantics) to your printer while you had the
