console 4 devices FreeBSD freebsd-console system console device The /dev/console device provides access to the FreeBSD console. What the console actually is can vary. The kernel maintains a list of console devices. The /dev/console device maps to the first device in the list. (Thus application output via /dev/console differs from kernel console message output, which goes to all devices listed.) The kernel's list of console devices is in the kern.console kernel state variable, supplied to it by the bootstrap kernel loader8. This variable lists one or more serial port devices (see uart4 and sio4) or kernel virtual terminal devices (see syscons4 and vt4). /dev/console is a fully functional terminal device, with a line discipline. Its input and output are routed via the underlying device by the kernel. Process 1 commences execution with its standard input, output, and error file descriptors open to the console device, and the console device as the controlling terminal of its session. A devfs5 filesystem automatically gains a node named console that denotes this device. The /dev/console device filename for the system console is required in order to conform with the Single Unix Specification (per "Directory Structure and Devices"). This explicitly permits it to be a link to another device. FreeBSD does not implement it as a link, however. conscontrol1 A convenience tool for manipulating the kernel's console device list. sysctl1 Lower level access to kernel variables. syslog3 Opening /dev/console and writing messages there is an optional functionality of the syslog library. Documentation by Jonathan de Boyne Pollard