NAME

       ioctl_vt - ioctls for console terminal and virtual consoles

SYNOPSIS

       #include <linux/vt.h>  /* Definition of VT_* constants */
       #include <sys/ioctl.h>

       int ioctl(int fd, unsigned long op, void *argp);

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

                  struct vt_mode {
                      char  mode;    /* vt mode */
                      char  waitv;   /* if set, hang on writes if not active */
                      short relsig;  /* signal to raise on release op */
                      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_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

                  struct vt_stat {
                      unsigned short v_active;  /* active vt */
                      unsigned short v_signal;  /* signal to send */
                      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

                  struct vt_sizes {
                      unsigned short v_rows;       /* # rows */
                      unsigned short v_cols;       /* # columns */
                      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

                  struct vt_consize {
                      unsigned short v_rows;  /* number of rows */
                      unsigned short v_cols;  /* number of columns */
                      unsigned short v_vlin;  /* number of pixel rows
                                                 on screen */
                      unsigned short v_clin;  /* number of pixel rows
                                                 per character */
                      unsigned short v_vcol;  /* number of pixel columns
                                                 on screen */
                      unsigned short 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 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)