vt_disallocate(2const)

NAME#

ioctl_vt - ioctls for console terminal and virtual consoles

SYNOPSIS#

#include <linux/vt.h>\n  /* Definition of \nVT_*\n constants */
\n#include <sys/ioctl.h>

int ioctl(int \nfd\n, unsigned long \nop\n, void *\nargp\n);

DESCRIPTION#

The following Linux-specific ioctl(2) operations are supported for console terminals and virtual consoles.

VT_OPENQRY

Returns 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_GETMODE

Get mode of active vt. argp points to a

bash

struct vt_mode {
\n
    char  mode;    /* vt mode */
\n
    char  waitv;   /* if set, hang on writes if not active */
\n
    short relsig;  /* signal to raise on release op */
\n
    short acqsig;  /* signal to raise on acquisition */
\n
    short frsig;   /* unused (set to 0) */
};

VT_AUTO	auto vt switching
VT_PROCESS	process controls switching
VT_ACKACQ	acknowledge switch

VT_SETMODE

Set mode of active vt. argp points to a struct vt_mode.

VT_GETSTATE

Get global vt state info. argp points to a

bash

struct vt_stat {
\n
    unsigned short v_active;  /* active vt */
\n
    unsigned short v_signal;  /* signal to send */
\n
    unsigned short v_state;   /* vt bit mask */
};

For each vt in use, the corresponding bit in the v_state member is set. (Linux 1.0 through Linux 1.1.92.)

VT_RELDISP

Release a display.

VT_ACTIVATE

Switch to vt argp (1 <= argp <= MAX_NR_CONSOLES).

VT_WAITACTIVE

Wait until vt argp has been activated.

VT_DISALLOCATE

Deallocate the memory associated with vt argp. (Since Linux 1.1.54.)

VT_RESIZE

Set the kernel's idea of screensize. argp points to a

bash

struct vt_sizes {
\n
    unsigned short v_rows;       /* # rows */
\n
    unsigned short v_cols;       /* # columns */
\n
    unsigned short v_scrollsize; /* no longer used */
};

Note that this does not change the videomode. See resizecons(8). (Since Linux 1.1.54.)

VT_RESIZEX

Set the kernel's idea of various screen parameters. argp points to a

bash

struct vt_consize {
\n
    unsigned short v_rows;  /* number of rows */
\n
    unsigned short v_cols;  /* number of columns */
\n
    unsigned short v_vlin;  /* number of pixel rows
\n
                               on screen */
\n
    unsigned short v_clin;  /* number of pixel rows
\n
                               per character */
\n
    unsigned short v_vcol;  /* number of pixel columns
\n
                               on screen */
\n
    unsigned short v_ccol;  /* number of pixel columns
\n
                               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 Linux 1.3.3.)

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.

STANDARDS#

Linux.

SEE ALSO#

ioctl(2), ioctl_console(2)