TIOCLINUX(2const)

NAME
TIOCLINUX - ioctls for console terminal and virtual consoles

SYNOPSIS
#include <linux/tiocl.h>  /* Definition of TIOCL_* constants */
#include <sys/ioctl.h>

int ioctl(int fd, TIOCLINUX, void *argp);

DESCRIPTION
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 terminal.

subcode=0
    Dump the screen. Disappeared in Linux 1.1.92. (With Linux 1.1.92 or later, read from /dev/vcsN or /dev/vcsaN instead.)

subcode=1
    Get task information. Disappeared in Linux 1.1.92.

subcode=TIOCL_SETSEL
    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 a kernel buffer.

    Since Linux 6.7, using this subcode requires the CAP_SYS_ADMIN capability.

subcode=TIOCL_PASTESEL
    Paste selection. The characters in the selection buffer are written to fd.

    Since Linux 6.7, using this subcode requires the CAP_SYS_ADMIN capability.

subcode=TIOCL_UNBLANKSCREEN
    Unblank the screen.

subcode=TIOCL_SELLOADLUT
    Sets contents of a 256-bit look up table defining characters in a "word", for word-by-word selection. (Since Linux 1.1.32.)

    Since Linux 6.7, using this subcode requires the CAP_SYS_ADMIN capability.

subcode=TIOCL_GETSHIFTSTATE
    argp points to a char which is set to the value of the kernel variable shift_state. (Since Linux 1.1.32.)

subcode=TIOCL_GETMOUSEREPORTING
    argp points to a char which is set to the value of the kernel variable report_mouse. (Since Linux 1.1.33.)

subcode=8
    Dump screen width and height, cursor position, and all the character-attribute pairs. (Linux 1.1.67 through Linux 1.1.91 only. With Linux 1.1.92 or later, read from /dev/vcsa* instead.)

subcode=9
    Restore screen width and height, cursor position, and all the character-attribute pairs. (Linux 1.1.67 through Linux 1.1.91 only. With Linux 1.1.92 or later, write to /dev/vcsa* instead.)

subcode=TIOCL_SETVESABLANK
    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 Linux 1.1.76.)

subcode=TIOCL_SETKMSGREDIRECT
    Change target of kernel messages ("console"): by default, and if this is set to 0, messages are written to the currently active VT. The VT to write to is a single byte following subcode. (Since Linux 2.5.36.)

subcode=TIOCL_GETFGCONSOLE
    Returns the number of VT currently in foreground. (Since Linux 2.5.36.)

subcode=TIOCL_SCROLLCONSOLE
    Scroll the foreground VT by the specified amount of lines down, or half the screen if 0. lines is *(((int32_t *)&subcode) + 1). (Since Linux 2.5.67.)

subcode=TIOCL_BLANKSCREEN
    Blank the foreground VT, ignoring "pokes" (typing): can only be unblanked explicitly (by switching VTs, to text mode, etc.). (Since Linux 2.5.71.)

subcode=TIOCL_BLANKEDSCREEN
    Returns the number of VT currently blanked, 0 if none. (Since Linux 2.5.71.)

subcode=16
    Never used.

subcode=TIOCL_GETKMSGREDIRECT
    Returns target of kernel messages. (Since Linux 2.6.17.)

RETURN VALUE
On success, 0 is returned (except where indicated). On failure, -1 is returned, and errno is set to indicate the error.

ERRORS

EINVAL
    argp is invalid.

EPERM
    Insufficient permission.

STANDARDS
Linux.

SEE ALSO
ioctl(2), ioctl_console(2)