resizecons - change kernel idea of the console size
resizecons -lines ROWS
command tries to change the videomode of the console.
There are several aspects to this: (a) the kernel must know about it, (b) the
hardware must know about it, (c) user programs must know about it, (d) the
console font may have to be adapted.
(a) The kernel is told about the change using the ioctl VT_RESIZE. This causes
the kernel to reallocate console screen memory for all virtual consoles, and
might fail if there is not enough memory. (In that case, try to disallocate
some virtual consoles first.) If this ioctl succeeds, but a later step fails
(e.g., because you do not have root permissions), you may be left with a very
The most difficult part of this is (b), since it requires detailed knowledge of
the video card hardware, and the setting of numerous registers. Only changing
the number of rows is slightly easier, and resizecons
will try to do
that itself, when given the -lines
option. (Probably, root permission
will be required.) The command resizecons COLSxROWS
restoretextmode -r COLSxROWS
(and hence requires that you have svgalib
installed). Here COLSxROWS is a file that was created earlier by
restoretextmode -w COLSxROWS.
Again, either root permissions are
required, or restoretextmode
has to be suid root.
In order to deal with (c), resizecons
does a `stty rows ROWS cols COLS'
for each active console (in the range tty0..tty15), and sends a SIGWINCH
signal to selection
if it finds the file /tmp/selection.pid.
Finally, (d) is dealt with by executing a setfont
command. Most likely,
the wrong font is loaded, and you may want to do another setfont
does not work on all hardware. For example, it cannot be used
on platforms other than x86 and x86_64. See the fbset
(1) program if you
are looking for an alternative.
This command used to be called resize,
but was renamed to avoid conflict
with another command with the same name.