---
name: "ttyS"
section: "4"
platform: "linux"
package: "man-pages"
version: "6.19-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/ttyS"
---

# ttyS(4)

serial terminal lines

## NAME

ttyS - serial terminal lines

## DESCRIPTION

**ttyS\[0-3\]** are character devices for the serial terminal lines.

They are typically created by:

```
mknod -m 660 /dev/ttyS0 c 4 64 # base address 0x3f8
mknod -m 660 /dev/ttyS1 c 4 65 # base address 0x2f8
mknod -m 660 /dev/ttyS2 c 4 66 # base address 0x3e8
mknod -m 660 /dev/ttyS3 c 4 67 # base address 0x2e8
chown root:tty /dev/ttyS[0-3]
```

## FILES

*/dev/ttyS\[0-3\]*

## SEE ALSO

[**chown**(1)](/chown/1.md), [**mknod**(1)](/mknod/1.md), [**tty**(4)](/tty/4.md), [**agetty**(8)](/agetty/8.md), [**mingetty**(8)](/mingetty/8.md), [**setserial**(8)](/setserial/8.md)