Xephyr(1) General Commands Manual Xephyr(1)
NAME
Xephyr - X server outputting to a window on a pre-existing X display
SYNOPSIS
Xephyr [:display] [option ...]
DESCRIPTION
Xephyr is a kdrive server that outputs to a window on a pre-existing
"host" X display. Think Xnest but with support for modern extensions
like composite, damage and randr.
Unlike Xnest which is an X proxy, i.e. limited to the capabilities of
the host X server, Xephyr is a real X server which uses the host X
server window as "framebuffer" via fast SHM XImages.
It also has support for "visually" debugging what the server is paint-
ing.
OPTIONS
The server accepts all the standard options of Xserver(1) and the fol-
lowing additional options:
-screen widthxheight
sets the screen size.
-parent id
uses existing window id . If a -screen argument follows a
-parent argument, this screen is embedded into the given win-
dow.
-host-cursor
set 'cursor acceleration': The host's cursor is reused. This is
only really there to aid debugging by avoiding server paints
for the cursor. Performance improvement is negligible.
-resizeable
Allow the Xephyr window to be resized, even if not embedded
into a parent window. By default, the Xephyr window has a fixed
size.
-no-host-grab
Disable grabbing the keyboard and mouse.
SIGNALS
Send a SIGUSR1 to the server (e.g. pkill -USR1 Xephyr) to toggle the
debugging mode. In this mode red rectangles are painted to screen ar-
eas getting painted before painting the actual content. The delay be-
tween this can be altered by setting a XEPHYR_PAUSE env var to a value
in micro seconds.
CAVEATS
• Rotated displays are currently updated via full blits. This is slower
than a normal orientated display. Debug mode will therefore not be of
much use rotated.
• The '-host-cursor' cursor is static in its appearance.
• The build gets a warning about 'nanosleep'. I think the various '-D'
build flags are causing this. I haven't figured as yet how to work
round it. It doesn't appear to break anything however.
• Keyboard handling is basic but works.
• Mouse button 5 probably won't work.
SEE ALSO
X(7), Xserver(1)
AUTHOR
Matthew Allum <mallum@o-hand.com> 2004
X Version 11 xorg-server 21.1.4 Xephyr(1)
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