rauletta@gmuvax2.gmu.edu (R. J. Auletta) (02/04/91)
We have a VS2000 (Ultrix 3.1) which boots
requiring modem signals on tty02. Since we wish
to use the serial port as a printer port we
have getty disabled and have run the following program.
(Which should permanently disable modem control.)
But when the system reboots, the port once again
requires modem signals to avoid having writes block.
Any suggestions? What's missing? Is this ioctl broken?
-R J Auletta
#include <sys/ioctl.h>
main()
{
int fd;
int turnoff = 1;
int error = 0;
fd = open("/dev/tty02",O_NDELAY | O_RDWR);
error = ioctl(fd, TIOCNMODEM, &turnoff);
fd = open("/dev/tty03",O_NDELAY | O_RDWR);
error = ioctl(fd, TIOCNMODEM, &turnoff);
}frank@croton.enet.dec.com (Frank Wortner) (02/05/91)
> ... we > have getty disabled and have run the following program. > (Which should permanently disable modem control.) > But when the system reboots, the port once again > requires modem signals to avoid having writes block. Unfortunately, "permanent" in this case means "until the next reboot." I'm not trying to be funny or snotty here, I mean exactly what I wrote. I don't believe the interface's state information is preserved across reboots. Frank
D. Allen [CGL]) (02/10/91)
In article <1893@riscy.enet.dec.com> frank@croton.enet.dec.com (Frank Wortner) writes: > >> ... we >> have getty disabled and have run the following program. >> (Which should permanently disable modem control.) >> But when the system reboots, the port once again >> requires modem signals to avoid having writes block. Won't the "flags" word in your kernel sys/conf/ config file let you permanently turn on/off the modem bits on your hard lines? device ss0 at uba0 csr 0x200a0000 flags 0x0f vector ssrint ssxint "man ss" will help. -- -IAN! (Ian! D. Allen) idallen@watcgl.uwaterloo.ca idallen@watcgl.waterloo.edu [129.97.128.64] Computer Graphics Lab/University of Waterloo/Ontario/Canada