comcontrol —
control a special tty device
The comcontrol utility is deprecated and
will be removed in FreeBSD 16.0.
comcontrol |
special_device [drainwait
number] |
The comcontrol utility is used to examine
and modify some of the special characteristics of the specified tty device.
If no arguments other than the device (or "-" for stdin) are
specified, it prints the settings of all controllable characteristics. This
usage requires only read access on the device. Only the superuser can change
the settings.
The following options are available:
drainwait
number
- Set the time to wait for output drain to the given number. The units are
seconds. The default is 5 minutes, 0 means waiting forever. This option is
needed mainly to specify an upper limit of minutes to prevent modem
hanging.
The standard way to use comcontrol is to
put invocations of it in the /etc/rc.d/serial
startup script.
- /dev/ttyd?
- dialin devices, hardwired terminals
- /dev/cuau?
- dialout devices
Originally part of cgd's com package patches, version 0.2.1, to
386BSD-0.1. Once controlled bidirectional
capabilities. Little is left to control now that these capabilities are
standard.