console ioctl — ioctl's for console terminal and virtual consoles
The following Linux-specific ioctl(2) requests are
supported. Each requires a third argument, assumed here to be
argp.
KDGETLEDGet state of LEDs. argp points to a long int. The lower
three bits of *argp are
set to the state of the LEDs, as follows:
LED_CAP0x04 caps lock led LEC_NUM0x02 num lock led LED_SCR0x01 scroll lock led
KDSETLEDSet the LEDs. The LEDs are set to correspond to the
lower three bits of argp.
However, if a higher order bit is set, the LEDs revert
to normal: displaying the state of the keyboard
functions of caps lock, num lock, and scroll lock.
Before 1.1.54, the LEDs just reflected the state of the corresponding keyboard flags, and KDGETLED/KDSETLED would also change the keyboard flags. Since 1.1.54 the leds can be made to display arbitrary information, but by default they display the keyboard flags. The following two ioctl's are used to access the keyboard flags.
KDGKBLEDGet keyboard flags CapsLock, NumLock, ScrollLock
(not lights). argp points
to a char which is set to the flag state. The low order
three bits (mask 0x7) get the current flag state, and
the low order bits of the next nibble (mask 0x70) get
the default flag state. (Since 1.1.54.)
KDSKBLEDSet keyboard flags CapsLock, NumLock, ScrollLock
(not lights). argp has
the desired flag state. The low order three bits (mask
0x7) have the flag state, and the low order bits of the
next nibble (mask 0x70) have the default flag state.
(Since 1.1.54.)
KDGKBTYPEGet keyboard type. This returns the value KB_101, defined as 0x02.
KDADDIOAdd I/O port as valid. Equivalent to ioperm(arg,1,1).
KDDELIODelete I/O port as valid. Equivalent to ioperm(arg,1,0).
KDENABIOEnable I/O to video board. Equivalent to ioperm(0x3b4, 0x3df-0x3b4+1, 1).
KDDISABIODisable I/O to video board. Equivalent to ioperm(0x3b4, 0x3df-0x3b4+1, 0).
KDSETMODESet text/graphics mode. argp is one of these:
KD_TEXT0x00 KD_GRAPHICS0x01
KDGETMODEGet text/graphics mode. argp points to a long which is set to
one of the above values.
KDMKTONEGenerate tone of specified length. The lower 16 bits
of argp specify the
period in clock cycles, and the upper 16 bits give the
duration in msec. If the duration is zero, the sound is
turned off. Control returns immediately. For example,
argp = (125<<16) +
0x637 would specify the beep normally associated with a
ctrl-G. (Thus since 0.99pl1; broken in 2.1.49-50.)
KIOCSOUNDStart or stop sound generation. The lower 16 bits of
argp specify the period
in clock cycles (that is, argp = 1193180/frequency).
argp = 0 turns sound off.
In either case, control returns immediately.
GIO_CMAPGet the current default color map from kernel.
argp points to a 48-byte
array. (Since 1.3.3.)
PIO_CMAPChange the default text-mode color map. argp points to a 48-byte array which
contains, in order, the Red, Green, and Blue values for
the 16 available screen colors: 0 is off, and 255 is
full intensity. The default colors are, in order:
black, dark red, dark green, brown, dark blue, dark
purple, dark cyan, light grey, dark grey, bright red,
bright green, yellow, bright blue, bright purple,
bright cyan and white. (Since 1.3.3.)
GIO_FONTGets 256-character screen font in expanded form.
argp points to an 8192
byte array. Fails with error code EINVAL if the currently loaded font
is a 512-character font, or if the console is not in
text mode.
GIO_FONTXGets screen font and associated information.
argp points to a
struct
consolefontdesc (see PIO_FONTX). On call, the charcount field should be set to the
maximum number of characters that would fit in the
buffer pointed to by chardata. On return, the charcount and charheight are filled with the
respective data for the currently loaded font, and the
chardata array contains
the font data if the initial value of charcount indicated enough space was
available; otherwise the buffer is untouched and
errno is set to
ENOMEM. (Since
1.3.1.)
PIO_FONTSets 256-character screen font. Load font into the
EGA/VGA character generator. argp points to a 8192 byte map, with
32 bytes per character. Only first N of them are used for an
8xN font (0 <
N <= 32). This call
also invalidates the Unicode mapping.
PIO_FONTXSets screen font and associated rendering
information. argp points
to a
| struct | consolefontdesc { | |||
| u_short | charcount; |
/* characters in font (256 or 512) */
|
||
| u_short | charheight; |
/* scan lines per character (1-32) */
|
||
| char | * | chardata; |
/* font data in expanded form */
|
|
| }; | ||||
If necessary, the screen will be appropriately
resized, and SIGWINCH
sent to the appropriate processes. This call also
invalidates the Unicode mapping. (Since 1.3.1.)
PIO_FONTRESETResets the screen font, size and Unicode mapping to
the bootup defaults. argp
is unused, but should be set to NULL to ensure
compatibility with future versions of Linux. (Since
1.3.28.)
GIO_SCRNMAPGet screen mapping from kernel. argp points to an area of size
E_TABSZ, which is loaded with the font positions used
to display each character. This call is likely to
return useless information if the currently loaded font
is more than 256 characters.
GIO_UNISCRNMAPGet full Unicode screen mapping from kernel.
argp points to an area of
size E_TABSZ*sizeof(unsigned short), which is loaded
with the Unicodes each character represent. A special
set of Unicodes, starting at U+F000, are used to
represent "direct to font" mappings. (Since 1.3.1.)
PIO_SCRNMAPLoads the "user definable" (fourth) table in the
kernel which maps bytes into console screen symbols.
argp points to an area of
size E_TABSZ.
PIO_UNISCRNMAPLoads the "user definable" (fourth) table in the kernel which maps bytes into Unicodes, which are then translated into screen symbols according to the currently loaded Unicode-to-font map. Special Unicodes starting at U+F000 can be used to map directly to the font symbols. (Since 1.3.1.)
GIO_UNIMAPGet Unicode-to-font mapping from kernel.
argp points to a
| struct | unimapdesc { | |||
| u_short | entry_ct; |
|||
| struct unipair | * | entries; |
||
| }; | ||||
where entries points to an
array of
| struct | unipair { | |||
| u_short | unicode; |
|||
| u_short | fontpos; |
|||
| }; | ||||
(Since 1.1.92.)
PIO_UNIMAPPut unicode-to-font mapping in kernel. argp points to a struct unimapdesc. (Since
1.1.92)
PIO_UNIMAPCLRClear table, possibly advise hash algorithm.
argp points to a
| struct | unimapinit { | |||
| u_short | advised_hashsize; |
/* 0 if no opinion */
|
||
| u_short | advised_hashstep; |
/* 0 if no opinion */
|
||
| u_short | advised_hashlevel; |
/* 0 if no opinion */
|
||
| }; | ||||
(Since 1.1.92.)
KDGKBMODEGets current keyboard mode. argp points to a long which is set to
one of these:
K_RAW0x00 K_XLATE0x01 K_MEDIUMRAW0x02 K_UNICODE0x03
KDSKBMODESets current keyboard mode. argp is a long equal to one of the
above values.
KDGKBMETAGets meta key handling mode. argp points to a long which is set to
one of these:
K_METABIT0x03 set high order bit K_ESCPREFIX0x04 escape prefix
KDSKBMETASets meta key handling mode. argp is a long equal to one of the
above values.
KDGKBENTGets one entry in key translation table (keycode to
action code). argp points
to a
| struct | kbentry { | |||
| u_char | kb_table; |
|||
| u_char | kb_index; |
|||
| u_short | kb_value; |
|||
| }; | ||||
with the first two members filled in: kb_table selects the key
table (0 <= kb_table <
MAX_NR_KEYMAPS), and kb_index is the keycode
(0 <= kb_index < NR_KEYS).
kb_value is set
to the corresponding action code, or K_HOLE if there is
no such key, or K_NOSUCHMAP if kb_table is invalid.
KDSKBENTSets one entry in translation table. argp points to a struct kbentry.
KDGKBSENTGets one function key string. argp points to a
| struct | kbsentry { | |||
| u_char | kb_func; |
|||
| u_char | kb_string[512]; |
|||
| }; | ||||
kb_string is
set to the (NULL terminated) string corresponding to
the kb_functh
function key action code.
KDSKBSENTSets one function key string entry. argp points to a struct kbsentry.
KDGKBDIACRRead kernel accent table. argp points to a
| struct | kbdiacrs { | |||
| unsigned int | kb_cnt; |
|||
| struct kbdiacr | kbdiacr[256]; |
|||
| }; | ||||
where kb_cnt
is the number of entries in the array, each of which is
a
| struct | kbdiacr { | |||
| u_char | diacr; |
|||
| u_char | base; |
|||
| u_char | result; |
|||
| }; | ||||
KDGETKEYCODERead kernel keycode table entry (scan code to
keycode). argp points to
a
| struct | kbkeycode { | |||
| unsigned int | scancode; |
|||
| unsigned int | keycode; |
|||
| }; | ||||
keycode is
set to correspond to the given scancode. (89 <=
scancode <=
255 only. For 1 <= scancode <= 88,
keycode==scancode.) (Since
1.1.63.)
KDSETKEYCODEWrite kernel keycode table entry. argp points to a struct kbkeycode. (Since
1.1.63.)
KDSIGACCEPTThe calling process indicates its willingness to
accept the signal argp
when it is generated by pressing an appropriate key
combination. (1 <= argp <= NSIG). (See
spawn_console() in linux/drivers/char/keyboard.c.)
VT_OPENQRYReturns the first available (non-opened) console.
argp points to an int
which is set to the number of the vt (1 <=
*argp <=
MAX_NR_CONSOLES).
VT_GETMODEGet mode of active vt. argp points to a
| struct | vt_mode { | |||
| char | mode; |
/* vt mode */
|
||
| char | waitv; |
/* if set, hang on writes if not active */
|
||
| short | relsig; |
/* signal to raise on release req */
|
||
| short | acqsig; |
/* signal to raise on acquisition */
|
||
| short | frsig; |
/* unused (set to 0) */
|
||
| }; | ||||
which is set to the mode of the active vt.
mode is set to
one of these values:
VT_AUTOauto vt switching VT_PROCESSprocess controls switching VT_ACKACQacknowledge switch
VT_SETMODESet mode of active vt. argp points to a struct vt_mode.
VT_GETSTATEGet global vt state info. argp points to a
| struct | vt_stat { | |||
| ushort | v_active; |
/* active vt */
|
||
| ushort | v_signal; |
/* signal to send */
|
||
| ushort | v_state; |
/* vt bit mask */
|
||
| }; | ||||
For each vt in use, the corresponding bit in the
v_state member
is set. (Kernels 1.0 through 1.1.92.)
VT_RELDISPRelease a display.
VT_ACTIVATESwitch to vt argp (1
<= argp <=
MAX_NR_CONSOLES).
VT_WAITACTIVEWait until vt argp has
been activated.
VT_DISALLOCATEDeallocate the memory associated with vt
argp. (Since 1.1.54.)
VT_RESIZESet the kernel's idea of screensize. argp points to a
| struct | vt_sizes { | |||
| ushort | v_rows; |
/* # rows */
|
||
| ushort | v_cols; |
/* # columns */
|
||
| ushort | v_scrollsize; |
/* no longer used */
|
||
| }; | ||||
Note that this does not change the videomode. See resizecons(8). (Since 1.1.54.)
VT_RESIZEXSet the kernel's idea of various screen parameters.
argp points to a
| struct | vt_consize { | |||
| ushort | v_rows; |
/* number of rows */
|
||
| ushort | v_cols; |
/* number of columns */
|
||
| ushort | v_vlin; |
/* number of pixel rows on screen */
|
||
| ushort | v_clin; |
/* number of pixel rows per character */
|
||
| ushort | v_vcol; |
/* number of pixel columns on screen */
|
||
| ushort | v_ccol; |
/* number of pixel columns per character */
|
||
| }; | ||||
Any parameter may be set to zero, indicating "no change", but if multiple parameters are set, they must be self-consistent. Note that this does not change the videomode. See resizecons(8). (Since 1.3.3.)
The action of the following ioctls depends on the first
byte in the struct pointed to by argp, referred to here as the subcode. These are legal only for the
superuser or the owner of the current tty.
Dump the screen. Disappeared in 1.1.92. (With kernel 1.1.92 or later, read from /dev/vcsN or /dev/vcsaN instead.)
Get task information. Disappeared in 1.1.92.
Set selection. argp
points to a
| struct | { | |||
| char | subcode; |
|||
| short | xs, |
|||
ys, |
||||
xe, |
||||
ye; |
||||
| short | sel_mode; |
|||
| }; | ||||
xs and
ys are the
starting column and row. xe and ye are the ending column
and row. (Upper left corner is row=column=1.)
sel_mode is 0
for character-by-character selection, 1 for
word-by-word selection, or 2 for line-by-line
selection. The indicated screen characters are
highlighted and saved in the static array sel_buffer in
devices/char/console.c.
Paste selection. The characters in the selection
buffer are written to fd.
Unblank the screen.
Sets contents of a 256-bit look up table defining characters in a "word", for word-by-word selection. (Since 1.1.32.)
argp points to a char
which is set to the value of the kernel variable
shift_state. (Since
1.1.32.)
argp points to a char
which is set to the value of the kernel variable
report_mouse. (Since
1.1.33.)
Dump screen width and height, cursor position, and all the character-attribute pairs. (Kernels 1.1.67 through 1.1.91 only. With kernel 1.1.92 or later, read from /dev/vcsa* instead.)
Restore screen width and height, cursor position, and all the character-attribute pairs. (Kernels 1.1.67 through 1.1.91 only. With kernel 1.1.92 or later, write to /dev/vcsa* instead.)
Handles the Power Saving feature of the new
generation of monitors. VESA screen blanking mode is
set to argp[1], which
governs what screen blanking does:
0: Screen blanking is
disabled.
1: The current video
adapter register settings are saved, then the
controller is programmed to turn off the vertical
synchronization pulses. This puts the monitor into
"standby" mode. If your monitor has an Off_Mode timer,
then it will eventually power down by itself.
2: The current
settings are saved, then both the vertical and
horizontal synchronization pulses are turned off. This
puts the monitor into "off" mode. If your monitor has
no Off_Mode timer, or if you want your monitor to power
down immediately when the blank_timer times out, then
you choose this option. (Caution: Powering down
frequently will damage the monitor.)
(Since 1.1.76.)
errno may take on these
values:
The file descriptor is invalid.
ENOTTY The file descriptor is not associated with a character special device, or the specified request does not apply to it.
The file descriptor or argp is invalid.
Insufficient permission.
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Warning |
|---|---|
|
Do not regard this man page as documentation of the Linux console ioctl's. This is provided for the curious only, as an alternative to reading the source. Ioctl's are undocumented Linux internals, liable to be changed without warning. (And indeed, this page more or less describes the situation as of kernel version 1.1.94; there are many minor and not-so-minor differences with earlier versions.) |
Very often, ioctl's are introduced for communication between the kernel and one particular well-known program (fdisk, hdparm, setserial, tunelp, loadkeys, selection, setfont, etc.), and their behavior will be changed when required by this particular program.
Programs using these ioctl's will not be portable to other versions of Unix, will not work on older versions of Linux, and will not work on future versions of Linux.
Use POSIX functions.
dumpkeys(1), kbd_mode(1), loadkeys(1), mknod(1), setleds(1), setmetamode(1), execve(2), fcntl(2), ioperm(2), termios(3), console(4), console_codes(4),
mt(4), sd(4), tty(4), tty_ioctl(4), ttyS(4), vcs(4), vcsa(4), charsets(7), mapscrn(8), resizecons(8), setfont(8), /usr/include/linux/kd.h, /usr/include/linux/vt.h
This page is part of release 2.74 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.
|
Copyright (c) 1995 Jim Van Zandt <jrvvanzandt.mv.com> and aeb Sun Feb 26 11:46:23 MET 1995 This is free documentation; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. The GNU General Public License's references to "object code" and "executables" are to be interpreted as the output of any document formatting or typesetting system, including intermediate and printed output. This manual is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this manual; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA. Modified, Sun Feb 26 15:04:20 1995, faithcs.unc.edu Modified, Thu Apr 20 22:08:17 1995, jrvvanzandt.mv.com Modified, Mon Sep 18 22:32:47 1995, hpastorm.net (H. Peter Anvin) " |