== xss ==

xss uses the nearly 20-year-old MIT-SCREEN-SAVER extension to launch a
program when the X server turns on the built-in screen saver.

xsswin makes a full-screen black window and runs some other program,
passing along the window ID in the environment ($XSS_WINDOW) and
possibly as an argument (XSS_WINDOW gets replaced with the id).

xcursorpos prints out the x and y coordinates of the cursor.

Examples
--------

Tell the X server to launch the screen saver after 90 seconds idle:

    xset s 90


Run like xautolock:

    xss xlock -mode qix &


Run like xscreensaver (no locking):

    xss xsswin /usr/lib/xscreensaver/flurry -window-id XSS_WINDOW


Shell script to run an xscreensaver hack and xtrlock at the same time,
but prevent locking if the cursor is in the upper-left corner:

    #! /bin/sh
    
    xcursorpos | (read x y; [ $x -lt 20 -a $y -lt 20 ]) && exit 0
    xsswin /usr/lib/xscreensaver/qix -window-id XSS_WINDOW &
    pid=$!
    xtrlock
    kill $pid


History
-------

AIX apparently had something also called `xss` which did almost exactly
what my xss does, but had some command-line options.

I'm not aware of anything else like `xsswin`.

I lifted some code from `beforelight` from the X11 distribution, and
from `slock` from [suckless.org](http://suckless.org/).  Both have a
BSD/X11-like license.


------

Neale Pickett <neale@woozle.org>