---
name: "slattach"
section: "8"
platform: "linux"
package: "net-tools"
version: "2.10-3"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/slattach"
---

# slattach(8)

attach a network interface to a serial line

## NAME

slattach - attach a network interface to a serial line

## SYNOPSIS

**slattach \[-dehlLmnqv\] \[-c command\] \[-p proto\] \[-s speed\] \[tty\]**\

## DESCRIPTION

**Slattach** is a tiny little program that can be used to put a normal terminal ("serial") line into one of several "network" modes, thus allowing you to use it for point-to-point links to other computers.

## OPTIONS

- **tty**

  Path to a serial device like */dev/ttyS\**, */dev/cua\** or */dev/ptmx* to spawn a new pseudo tty.

- **\[-c command\]**

  Execute **command** when the line is hung up. This can be used to run scripts or re-establish connections when a link goes down.

- **\[-d\]**

  Enable debugging output.  Useful when determining why a given setup doesn't work.

- **\[-h\]**

  Exit when the carrier is lost. This works on both /dev/tty and /dev/cua devices by directly monitoring the carrier status every 15 seconds.

- **\[-v\]**

  Enable verbose output.  Useful in shell scripts.

- **\[-q\]**

  Operate in quiet mode - no messages at all.

- **\[-l\]**

  Create an UUCP-style lockfile for the device in /var/lock.

- **\[-n\]**

  Equivalent to the "mesg n" command.

- **\[-m\]**

  Do **not** initialize the line into 8 bits raw mode.

- **\[-e\]**

  Exit right after initializing device, instead of waiting for the line to hang up.

- **\[-L\]**

  Enable 3 wire operation. The terminal is moved into CLOCAL mode,  carrier watching is disabled.

- **\[-p proto\]**

  Set a specific kind of protocol to use on the line.  The default is set to **cslip**, i.e. compressed SLIP.  Other possible values are **slip** (normal SLIP),  **adaptive** (adaptive CSLIP/SLIP), **ppp** (Point-to-Point Protocol) and **kiss** (a protocol used for communicating with AX.25 packet radio terminal node controllers). The special argument **tty** can be used to put the device back into normal serial operation. Using 'ppp' mode is not normally useful as ppp requires an additional ppp daemon **pppd** to be active on the line. For kiss connections the  **kissattach** program should be used.

- **\[-s speed\]**

  Set a specific line speed, other than the default.

If no arguments are given, the current terminal line (usually: the login device) is used.  Otherwise, an attempt is made to claim the indicated terminal port, lock it, and open it.

## FILES

*/dev/cua\* /var/lock/LCK.\* /dev/ttyS\* /dev/ptmx*

## BUGS

None known.

## SEE ALSO

[**kissattach**(8)](/kissattach/8.md), [**dip**(8)](/dip/8.md), [**pppd**(8)](/pppd/8.md), [**sliplogin**(8)](/sliplogin/8.md)

## AUTHORS

Fred N. van Kempen, \<waltje@uwalt.nl.mugnet.org\>\
 Alan Cox, \<Alan.Cox@linux.org\>\
 Miquel van Smoorenburg, \<miquels@drinkel.ow.org\>\
 George Shearer, \<gshearer@one.net\>\
 Yossi Gottlieb, \<yogo@math.tau.ac.il\>\