1CONSOLE(4) Linux Programmer's Manual CONSOLE(4)
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6 console - console terminal and virtual consoles
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9 A Linux system has up to 63 virtual consoles (character devices with
10 major number 4 and minor number 1 to 63), usually called /dev/ttyn with
11 1 ≤ n ≤ 63. The current console is also addressed by /dev/console or
12 /dev/tty0, the character device with major number 4 and minor number 0.
13 The device files /dev/* are usually created using the script MAKEDEV,
14 or using mknod(1), usually with mode 0622 and owner root.tty.
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16 Before kernel version 1.1.54 the number of virtual consoles was com‐
17 piled into the kernel (in tty.h: #define NR_CONSOLES 8) and could be
18 changed by editing and recompiling. Since version 1.1.54 virtual con‐
19 soles are created on the fly, as soon as they are needed.
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21 Common ways to start a process on a console are: (a) tell init(8) (in
22 inittab(5)) to start a mingetty(8) (or agetty(8)) on the console; (b)
23 ask openvt(1) to start a process on the console; (c) start X — it will
24 find the first unused console, and display its output there. (There is
25 also the ancient doshell(8).)
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27 Common ways to switch consoles are: (a) use Alt+Fn or Ctrl+Alt+Fn to
28 switch to console n; AltGr+Fn might bring you to console n+12 [here Alt
29 and AltGr refer to the left and right Alt keys, respectively]; (b) use
30 Alt+RightArrow or Alt+LeftArrow to cycle through the presently allo‐
31 cated consoles; (c) use the program chvt(1). (The key mapping is user
32 settable, see loadkeys(1); the above mentioned key combinations are
33 according to the default settings.)
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35 The command deallocvt(1) (formerly disalloc) will free the memory taken
36 by the screen buffers for consoles that no longer have any associated
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39 Properties
40 Consoles carry a lot of state. I hope to document that some other
41 time. The most important fact is that the consoles simulate vt100 ter‐
42 minals. In particular, a console is reset to the initial state by
43 printing the two characters ESC c. All escape sequences can be found
44 in console_codes(4).
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47 /dev/console
48 /dev/tty*
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51 chvt(1), deallocvt(1), loadkeys(1), mknod(1), openvt(1), con‐
52 sole_codes(4), console_ioctl(4), tty(4), ttyS(4), charsets(7),
53 agetty(8), init(8), mapscrn(8), mingetty(8), resizecons(8), setfont(8)
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56 This page is part of release 3.22 of the Linux man-pages project. A
57 description of the project, and information about reporting bugs, can
58 be found at http://www.kernel.org/doc/man-pages/.
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62Linux 1994-10-31 CONSOLE(4)