This file displays the various character and block devices currently configured (not including devices whose modules are not loaded). Below is a sample output from this file:
The output from
/proc/devices includes the major number and name of the device, and is broken into two major sections:
Character devices and
Character devices are similar to block devices, except for two basic differences:
Character devices do not require buffering. Block devices have a buffer available, allowing them to order requests before addressing them. This is important for devices designed to store information — such as hard drives — because the ability to order the information before writing it to the device allows it to be placed in a more efficient order.
Character devices send data with no preconfigured size. Block devices can send and receive information in blocks of a size configured per device.