.\" Copyright 2017, Michael Kerrisk <mtk.manpages@gmail.com>
.\" Copyright, the authors of the Linux man-pages project
.\"
.\" SPDX-License-Identifier: Linux-man-pages-copyleft
.\"
.TH sys_dev 5 2026-09-09 "Linux man-pages 6.20"
.SH NAME
/sys/dev/ \- system devices
.SH SYNOPSIS
.I /sys/dev/
.SH DESCRIPTION
This directory contains two subdirectories
.I block/
and
.IR char/ ,
corresponding, respectively,
to the block and character devices on the system.
Inside each of these subdirectories are symbolic links with names of the form
.IR major-ID : minor-ID ,
where the ID values correspond to the major and minor ID of a specific device.
Each symbolic link points to the
.B sysfs
directory for a device.
The symbolic links inside
.I /sys/dev/
thus provide an easy way to look up the
.B sysfs
interface using the device IDs returned by a call to
.BR stat (2)
(or similar).
.P
The following shell session shows an example from
.IR /sys/dev/ :
.P
.in +4n
.EX
.RB $ " stat \-c \[dq]%t %T\[dq] /dev/null" ;
1 3
.RB $ " readlink /sys/dev/char/1\[rs]:3" ;
\&../../devices/virtual/mem/null
.RB $ " ls \-Fd /sys/devices/virtual/mem/null" ;
/sys/devices/virtual/mem/null/
.RB $ " ls \-d1 /sys/devices/virtual/mem/null/*" ;
/sys/devices/virtual/mem/null/dev
/sys/devices/virtual/mem/null/power/
/sys/devices/virtual/mem/null/subsystem@
/sys/devices/virtual/mem/null/uevent
.EE
.in
.SH STANDARDS
Linux.
.SH HISTORY
Linux 2.6.0.
.SH SEE ALSO
.BR sysfs (5)