DEV(4FS) File Systems DEV(4FS)

NAME

dev - Device name file system

DESCRIPTION

The dev filesystem manages the name spaces of devices in the operating
system. The global zone's instance of the dev filesystem is mounted
during boot on /dev. This filesystem is colloquially called `sdev' as
a way to distinguish it from the devfs(4FS) filesystem mounted at
/devices.

A subdirectory under /dev may have unique operational semantics. Most
of the common device names under /dev are created automatically by
devfsadm(8) Others, such as /dev/pts, /dev/net, and /dev/zvol are
dynamic and reflect the operational state of the system. You can
manually generate device names for newly attached hardware by invoking
devfsadm(8) or implicitly, by indirectly causing a lookup or readdir
operation in the filesystem to occur. For example, you can discover a
disk that was attached when the system was powered down (and generate a
name for that device) by invoking format(8).

In a non-global zone, the dev filesystem is also mounted at /dev;
however, it is generally speaking read-only. Unlike in the global
zone, a privileged user in a non-global zone cannot create directories
or files, directories, or other objects within the filesystem.

FILES

/dev Mount point for the dev filesystem in
the global zone and non-global zones.

SEE ALSO

devfs(4FS), devfsadm(8), format(8)

NOTES

The global /dev instance cannot be unmounted.

illumos March 10, 2023 illumos