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    The following form allows you to view linux man pages.

    Command:

    vcs

    
    
    

    DESCRIPTION

           /dev/vcs0 is a character device with major number 7 and minor number 0,
           usually of mode 0644 and owner root.tty.  It refers to  the  memory  of
           the currently displayed virtual console terminal.
    
           /dev/vcs[1-63]  are  character  devices  for virtual console terminals,
           they have major number 7 and minor number 1 to 63,  usually  mode  0644
           and  owner  root.tty.  /dev/vcsa[0-63] are the same, but using unsigned
           shorts (in host byte order) that include attributes, and prefixed  with
           four  bytes  giving  the  screen dimensions and cursor position: lines,
           columns, x, y.  (x = y = 0 at the top left corner of the screen.)
    
           When a 512-character font is  loaded,  the  9th  bit  position  can  be
           fetched  by applying the ioctl(2) VT_GETHIFONTMASK operation (available
           in Linux kernels 2.6.18 and above)  on  /dev/tty[1-63];  the  value  is
           returned  in  the unsigned short pointed to by the third ioctl(2) argu-
           ment.
    
           These devices replace the screendump ioctl(2) operations of console(4),
           so the system administrator can control access using filesystem permis-
           sions.
    
           The devices for the first eight virtual consoles may be created by:
    
               for x in 0 1 2 3 4 5 6 7 8; do
                   mknod -m 644 /dev/vcs$x c 7 $x;
                   mknod -m 644 /dev/vcsa$x c 7 $[$x+128];
               done
               chown root:tty /dev/vcs*
    
           No ioctl(2) requests are supported.
    
    
    

    FILES

           /dev/vcs[0-63]
           /dev/vcsa[0-63]
    
    
    

    VERSIONS

           Introduced with version 1.1.92 of the Linux kernel.
    
    
    

    EXAMPLE

           You may do a screendump on vt3 by switching to vt1 and typing
    
               cat /dev/vcs3 >foo
    
           Note that the output does not contain newline characters, so some  pro-
           cessing may be required, like in
    
               old -w 81 /dev/vcs3 | lpr
    
           or (horrors)
    
               xetterm -dump 3 -file /proc/self/fd/1
    
           int
           main(void)
           {
               int fd;
               char *device = "/dev/vcsa2";
               char *console = "/dev/tty2";
               struct {unsigned char lines, cols, x, y;} scrn;
               unsigned short s;
               unsigned short mask;
               unsigned char ch, attrib;
    
               fd = open(console, O_RDWR);
               if (fd < 0) {
                   perror(console);
                   exit(EXIT_FAILURE);
               }
               if (ioctl(fd, VT_GETHIFONTMASK, &mask) < 0) {
                   perror("VT_GETHIFONTMASK");
                   exit(EXIT_FAILURE);
               }
               (void) close(fd);
               fd = open(device, O_RDWR);
               if (fd < 0) {
                   perror(device);
                   exit(EXIT_FAILURE);
               }
               (void) read(fd, &scrn, 4);
               (void) lseek(fd, 4 + 2*(scrn.y*scrn.cols + scrn.x), 0);
               (void) read(fd, &s, 2);
               ch = s & 0xff;
               if (attrib & mask)
                   ch |= 0x100;
               attrib = ((s & ~mask) >> 8);
               printf("ch='%c' attrib=0x%02x\n", ch, attrib);
               attrib ^= 0x10;
               (void) lseek(fd, -1, 1);
               (void) write(fd, &attrib, 1);
               exit(EXIT_SUCCESS);
           }
    
    
    

    SEE ALSO

           console(4), tty(4), ttyS(4), gpm(8)
    
    
    

    Linux 2007-12-17 VCS(4)

    
    
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