---
name: "dcons"
section: "4freebsd"
platform: "linux"
package: "freebsd-manpages"
version: "12.2-2"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/dcons/4freebsd"
---

# dcons(4freebsd)

dumb console device driver

## NAME

**dcons** – dumb console device driver

## SYNOPSIS

To compile this driver into the kernel, place the following lines in your kernel configuration file:

**options GDB** **device firewire** **device dcons**

Alternatively, to load the driver as a module at boot time, place the following line in your kernel configuration file:

**options GDB**

and in [loader.conf(5)](/loader.conf/5.md):

dcons\_load="YES"

## DESCRIPTION

The **dcons** device is a simple console device which just reads from and writes to an allocated buffer for input and output respectively. It is of no use by itself and it is supposed that the buffer is accessed via a bus like [firewire(4)](/firewire/4.md) or [kvm(3)](/kvm/3.md) for interaction.

The buffer consists of 4 channels. There are 2 ports, one for the console TTY and another is GDB port, then each port has an input channel and an output channel.

## FILES

- */dev/dcons*

  - */etc/ttys*

  ## EXAMPLES

If you want to run [getty(8)](/getty/8.md) on **dcons**, insert the following line into [ttys(5)](/ttys/5.md) and send a HUP signal to [init(8)](/init/8.md) using [kill(1)](/kill/1.md).

```
dcons	"/usr/libexec/getty std.9600"	vt100	on  secure
```

Once the [fwohci(4)](/fwohci/4.md) device is initialized to allow physical access, the buffer can be accessed from another host via a [firewire(4)](/firewire/4.md) bus using the [dconschat(8)](/dconschat/8.md) application. See [dconschat(8)](/dconschat/8.md) for more details.

If you want to use **dcons** as a [gdb(1)](/gdb/1.md) port, add the following line into [loader.conf(5)](/loader.conf/5.md):

```
dcons_gdb="1"
```

## SEE ALSO

[dcons\_crom(4)](/dcons_crom/4.md), [ddb(4)](/ddb/4.md), [firewire(4)](/firewire/4.md), [fwohci(4)](/fwohci/4.md), [gdb(4)](/gdb/4.md), [ttys(5)](/ttys/5.md), [conscontrol(8)](/conscontrol/8.md), [dconschat(8)](/dconschat/8.md), [fwcontrol(8)](/fwcontrol/8.md)

## AUTHORS

Hidetoshi Shimokawa ⟨*simokawa@FreeBSD.org*⟩

## BUGS

This driver is currently under development.