console

CONSOLE(4)                 Linux Programmer's Manual                CONSOLE(4)



NAME
       console - console terminal and virtual consoles

DESCRIPTION
       A Linux system has up to 63 virtual consoles (character devices with
       major number 4 and minor number 1 to 63), usually called /dev/ttyn with
       1 ≤ n ≤ 63.  The current console is also addressed by /dev/console or
       /dev/tty0, the character device with major number 4 and minor number 0.
       The device files /dev/* are usually created using the script MAKEDEV,
       or using mknod(1), usually with mode 0622 and owner root.tty.

       Before kernel version 1.1.54 the number of virtual consoles was
       compiled into the kernel (in tty.h: #define NR_CONSOLES 8) and could be
       changed by editing and recompiling.  Since version 1.1.54 virtual
       consoles are created on the fly, as soon as they are needed.

       Common ways to start a process on a console are: (a) tell init(1) (in
       inittab(5)) to start a mingetty(8) (or agetty(8)) on the console; (b)
       ask openvt(1) to start a process on the console; (c) start X—it will
       find the first unused console, and display its output there.  (There is
       also the ancient doshell(8).)

       Common ways to switch consoles are: (a) use Alt+Fn or Ctrl+Alt+Fn to
       switch to console n; AltGr+Fn might bring you to console n+12 [here Alt
       and AltGr refer to the left and right Alt keys, respectively]; (b) use
       Alt+RightArrow or Alt+LeftArrow to cycle through the presently
       allocated consoles; (c) use the program chvt(1).  (The key mapping is
       user settable, see loadkeys(1); the above mentioned key combinations
       are according to the default settings.)

       The command deallocvt(1) (formerly disalloc) will free the memory taken
       by the screen buffers for consoles that no longer have any associated
       process.

   Properties
       Consoles carry a lot of state.  I hope to document that some other
       time.  The most important fact is that the consoles simulate vt100
       terminals.  In particular, a console is reset to the initial state by
       printing the two characters ESC c.  All escape sequences can be found
       in console_codes(4).

FILES
       /dev/console
       /dev/tty*

SEE ALSO
       chvt(1), deallocvt(1), init(1), loadkeys(1), mknod(1), openvt(1),
       console_codes(4), console_ioctl(4), tty(4), ttyS(4), charsets(7),
       agetty(8), mapscrn(8), mingetty(8), resizecons(8), setfont(8)

COLOPHON
       This page is part of release 4.05 of the Linux man-pages project.  A
       description of the project, information about reporting bugs, and the
       latest version of this page, can be found at
       https://www.kernel.org/doc/man-pages/.



Linux                             1994-10-31                        CONSOLE(4)