The presence of a file does not necessarily mean that the corresponding device is attached to the computer.
For devices that contain partitionable file systems (such as the SCSI drive
/dev/sda, a device file for each partition is allocated (
/dev/sda1,
/dev/sda2 …).
acpi_thermal_rel | |
aio | Asynchronous I/O notification interface |
autofs | |
block/ | Compare with char/ |
btrfs-control | |
bus/ | |
char/ | Compare with block/ |
console | The device to which system messages shuld be sent. |
core | Obsolete, replaced by /proc/kcore |
cpu | /dev/cpu/<cpu-nr>/{cpuid,msr}, /dev/cpu/microcode |
cpu_dma_latency | |
cuse | |
disk/ | |
dri/ | Direct Rendering Infrastructure |
drm_dp_auxN | |
dxg | Emulation of the native WDDM D3DKMT kernel service layer on Windows (WSL?) |
fbN | Frame buffer |
fbN | |
fd/ | Symbolic link to /proc/self/fd. A directory with «file descriptors». Do not confuse with floppy disks. |
fdN | Floppy disk. Do not confuse with file descriptors. |
full | Returns ENOSPC when written to and zero-bytes when read from. |
fuse | |
gpiochipN | |
hdX | IDE disks. /dev/hda represents the first IDE drive in the system. My assumption is that hd simply stands for hard disk. Up to 63 partitions can be referenced, for example /dev/hda4. |
hidrawN | |
hpet | |
hugepages/ | Is a userspace API for allocating large (huge) memory pages |
hvcX | Hypervisor console X, used for Xen and PowerPC hypervisors? Or IBM iSeris/pSeries virtual console? |
hwrng | |
initrd | Initial RAM disk, compare with /dev/ramN |
input/ | |
kmsg | printk records |
kmem | Kernel virtual memory, compare with mem. |
kvm | Kernel-based virtual machine. |
log | On my machine: a symlink to /run/systemd/journal/dev-log |
loopX | Loopback devices |
loop-control | |
mapper/ | |
mediaN | |
meiN | |
mem | |
mqueue/ | |
lpN | Parallel printer (parport0) |
mcelog | Machine check entries (See also /sys/devices/system/machinecheck/machinecheckN and Documentation/arch/x86/x86_64/machinecheck.rst) |
mdN | Metadisk (RAID) - Used to span a fileystem accross multiple physical disks. |
mem | Physical memory access, compare with kmem. |
mmcblk… | MMC devices |
mqueue | mqueue IPC objects. |
net/ | |
null | The infamous null device, an empty data source and infinite data sink. Compare with /dev/zero |
nvme… | devices connected through NVM Express (NVMe) |
nvram | |
oldmem | Obsolete, replaced by /proc/vmcore |
port | I/O Port access |
ppp | |
psaux | |
ptmx | PTY master multiplex |
ptp0 | |
pts/ | |
ptypN | Pseudo-TTY masters (old style, BSD) |
ramN | RAM disk. Compare with /dev/initrd |
random | Non-deterministic random number generator, slower, but more secure than /dev/urandom |
rfkill | Turn off ratio transmission |
rtc | Real-time clock |
sdX | sd stands for SCSI disk. |
sgx_provision | |
sgx_vepc | |
shm/ | For named semaphores (and more?) |
snapshot | |
srX | Optical (SCSI?) devices (CD ROM) (r = read only?) ( |
stdin, stdout, stderr | Symbolic links to /proc/self/fd/{0,1,2}. See also STDIN, STDOUT and STDERR. |
snd/ | For sound devices? |
stN | (Character) SCSI tape device. |
stderr | symlink to /proc/self/fd/2 |
stdin | symlink to /proc/self/fd/0 |
stdout | symlink to /proc/self/fd/0 |
tpmN | TCPA TPM driver |
tpmrmN | |
tty | |
ttyN | Virtual console (tty0 is the current virtual console) |
ttySN | UART serial port |
ttypN | PTY slave |
uhid | |
uinput | |
urandom | Faster, but less seucre variant of /dev/random |
userfaultfd | |
vcs, vcsa, vcsu | virtual console screen and virtual console screen with attributes and Unicode. |
vcs | |
vcsN | ttyN text (glyph) contents. |
vcsa | |
vcsaN | ttyN attributes? |
vcsu | |
vcsuN | |
vfio/ | |
vfio/ | |
vga_arbiter | |
vhci | |
vhost-net | |
vhost-vsock | |
videoN | |
v41/ | |
watchdog | See also wdctl (part of util-linux). |
watchdogN | |
xvda | Xen Virtual Disk |
zero | Endless source of 0x00 bytes. Compare with /dev/null |