Manual Page Result
0
Command: nmdm | Section: 4 | Source: FreeBSD | File: nmdm.4.gz
NMDM(4) FreeBSD Kernel Interfaces Manual NMDM(4)
NAME
nmdm - nullmodem terminal driver
SYNOPSIS
To compile this driver into the kernel, place the following line in your
kernel configuration file:
device nmdm
Alternatively, to load the driver as a module at boot time, place the
following line in loader.conf(5):
nmdm_load="YES"
DESCRIPTION
The nmdm driver provides two tty(4) devices connected by a virtual "null
modem" cable.
If either of the two tty devices have the CDSR_OFLOW bit ("stty dsrflow")
set in their line discipline, the nmdm device will emulate the speed
configured in the termios(4) settings. The speed emulation works
independently in the two directions, controlled by the slower end's
termios settings (c_ispeed, c_ospeed, CS5 ... CS8, CSTOPB and PARENB).
FILES
/dev/nmdmN[AB] nullmodem device nodes. Where the A node
has a matching B node.
The nmdm driver implements "on-demand device creation" so simply
accessing a given instance in /dev will create it.
DIAGNOSTICS
None.
SEE ALSO
stty(1), termios(4), tty(4), ttys(5)
HISTORY
The nmdm driver first appeared in FreeBSD 4.4.
FreeBSD 14.1-RELEASE-p8 July 11, 2020 FreeBSD 14.1-RELEASE-p8