1.Dd December 10, 1993 2.Dt COMCONTROL 8 3.Os FreeBSD 4.Sh NAME 5.Nm comcontrol 6.Nd "control the bidirectional status of a sio port and waiting time after DTR drop" 7.Sh SYNOPSIS 8.Nm comcontrol 9.Ar sio_special_device 10.Op Cm bidir | Fl bidir 11.Op Cm dtrwait Ar ticks 12.Sh DESCRIPTION 13.Nm Comcontrol 14is used to examine and modify the bidirectional status 15of a specified 16sio communications port 17and its waiting time after DTR drop. 18By default (if 19.Ar sio_special_device 20only specified), 21.Nm comcontrol 22will print the current port state 23(if kernel was built with 24.Cm options COM_BIDIR ) 25as either 26.Cm bidir 27to indicate that bidirectional operation is enabled or 28.Fl bidir 29to indicate that it is disabled, string 30.Cm dtrwait 31and current waiting time in ticks 32after DTR drop. 33To modify the status of the port or waiting time, simply 34specify the desired new state 35and/or new waiting time 36on the command line. All users with 37read access to the 38.Ar sio_special_device 39can use 40.Nm comcontrol 41to get the port's status and current waiting time. 42Only root can set a port's status and waiting time. 43By default, each port is initially unidirectional, waiting time is 442 seconds. 45.Pp 46The standard way to use 47.Nm comcontrol 48is to put invocations of it in the 49.Ar /etc/rc.local 50startup script. 51.Sh SEE ALSO 52.Xr sio 4 53.Sh FILES 54.Bl -tag -width Pa 55.It Pa /dev/ttyd? 56.Sh DIAGNOSTICS 57.Cm TIOCMSBIDIR: Inappropriate ioctl for device. 58.Pp 59This indicates attempt to change port status on 60a non-sio special device file, 61or the kernel has not been built with 62.Cm options COM_BIDIR . 63For more information concerning reconfiguration 64of your kernel see 65.Ar /usr/src/sys/i386/doc/config_options.doc. 66.Sh AUTHOR 67Christopher G. Demetriou 68.Sh BUGS 69It is strongly recommended that you do *not* 70change the bidirectional status of a port while there are programs 71using the port. Read that as: if you do, and it breaks, don't yell 72at me; that's a really weird thing to do. 73.Sh HISTORY 74Originally part of cgd's com package patches, version 0.2.1, to 386BSD 0.1. 75