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.. RST source for unsaver(1) man page. Convert with:
..   rst2man.py unsaver.rst > unsaver.1

.. |version| replace:: 0.3.0
.. |date| date::

=======
unsaver
=======

-------------------------------------------
deactivate screensaver on joystick activity
-------------------------------------------

:Manual section: 1
:Manual group: Urchlay
:Date: |date|
:Version: |version|

SYNOPSIS
========

unsaver [**-i interval[s|ms]**] [**-m** | **-k keycode** | **-b button** | **-c command** | **-x** ] [**-d dir**] [**-j name**] [**-f**] [**-F**] [**-D**] [**joydev [joydev ...]**]

DESCRIPTION
===========

unsaver lets you play games with your joysticks/gamepads without the screen
saver activating due to lack of keyboard/mouse input. It can also prevent
the screensaver from activating when a fullscreen window is in use (e.g.
while watching a movie).

Multiple joystick devices can be monitored. By default, unsaver
monitors up to 16 devices, named /dev/input/js0 through js15.
These devices don't have to actually exist: they can come and go
as joysticks are plugged in and unplugged.

Every *interval* milliseconds (250, or whatever **-i** is set to), unsaver
checks to see if there's been any activity on any of the devices it's
monitoring. If so, it sends a fake mouse movement, keystroke, or mouse
button click, which the screen saver will see as activity.

It's recommended to let unsaver find the joysticks itself. However,
you can pass one or more device names (or just numbers) if the default
doesn't do the right thing for you. In this case, only these devices
will be monitored (no search is done).

unsaver should be started from your **.xinitrc** or whatever X startup
script your window manager or desktop environment uses. By default, it
will exit when the X server does. There's no PID file: use "pkill unsaver"
if you need to kill the daemon.

OPTIONS
=======

--help         Print usage summary

-i <interval>  Interval to check for activity. Can be given in seconds
               with *s* suffix (e.g. **1s**), or milliseconds with *m*
               (e.g. **200m**). If just a number is given, it's assumed
               to be in seconds if it's under 100, otherwise it's treated
               as milliseconds. Default: 250m.

-k <keycode>   Send this keycode when activity is detected. Default
               is to search the keymap for an unused code. If you set this
               manually, it should be a keycode that *doesn't* map to a keysym
               in your usual keymapping (use "xmodmap -pk" to find one).

-b <button>    Send a click of this button when activity is detected,
               rather than a keystroke. Should be a button that
               applications don't normally respond to (6 or higher),
               but in some environments, the window manager responds to
               all the 'extra' buttons as though they were button 1.

-m             Send mouse movements rather than a keystroke. This will
               move the pointer 10 pixels to the right and down, then
               10 pixels to the left and up, then warp the pointer back
               to its starting point.

-c <command>   Run a command when activity is detected, rather than
               sending a fake keystroke/click/motion. It's recommended
               to set *interval* to at least 1 second when using this
               option, to avoid excess process-spawning overhead.

-x             Same as **-c "xscreensaver-command -deactivate" -i 1s**.

-f             Deactivate screensaver if a fullscreen window is detected.
               This isn't likely to be 100% reliable yet.

-F             Same as **-f**, but also disables joystick monitoring entirely.
               Note that **-j**, **-d**, and **joydev** are ignored
               with this option.

These options are intended for developers and  *really* shouldn't be
needed for normal use:

-d <dir>       Path to the directory containing joystick device nodes.
               Default is "/dev/input". This directory is monitored with
               inotify(7) so unsaver will be aware of hotplug events.

-j <name>      Name of joystick device nodes, without any numeric
               suffix. Default is "js".

-D             Debug mode: run in foreground and print verbose messages.

A space is required between an option and its argument, as shown
above. Use e.g. **-i 300**, not **-i300**.

NOTES
=====

unsaver was tested with xlock(1) and xscreensaver(1). All 3 modes
(keycode, mouse click, and mouse motion) work with xscreensaver.
xlock doesn't respond to mouse motion, so use the keycode or click
modes with it.

unsaver can monitor up to MAX_STICKS joysticks. This is a compile time
constant, normally set to 16. See the **--help** output to find out
the compiled-in default.

**joydev** arguments can be either a path to a device node (e.g.
*/dev/input/js0* or similar), or a number, which will have the default
device basename prepended to it. This is normally "/dev/input/js", but
can be changed via the **-d** and **-j** options. Note that (currently)
all the joystick devices have to be in the same directory for unsaver
to detect hotplug events!

Note that it's *not* an error to give nonexistent joystick device names.
unsaver will wait for devices to come into existence (e.g. as created
by **udev**).

If the screensaver is configured to lock the screen, and it has already
done so, pressing a joystick button/direction will just bring up the
password dialog, same as pressing a key or mouse button would.

unsaver depends on the XTest extension being present in the X server. If
you get a "X server doesn't support XTest extension" error, see your X
server documentation to find out how to enable XTest.

The fullscreen window monitoring has only been tested on a system with
a single monitor, and may not work properly in multi-head environments.

EXIT STATUS
===========

Without the -D option, the exit status is 0 (success) if unsaver
successfully forked into the background.

A non-zero exit status means an error in the command line arguments,
or else fork() failed. No daemon will be running in this case.

With the -D option, unsaver never exits until it's killed.

BUGS
====

There's no way to distinguish between an invalid device name and a
device name that doesn't happen to exist yet because its device hasn't
been plugged in yet. Try to avoid typos, if you really have to use device
names (better to autodetect).

Normally once daemonized, unsaver is very robust. However, if something
does go wrong, there's no way to find out what. Probably there should
be a log file, or use syslog (or is that overkill?).

It should be (but currently isn't) possible to at least work in
mouse-motion mode even without the XTest extension, via XWarpPointer().

unsaver isn't portable. It only works on Linux, at least for now, for
three reasons:

- It uses the Linux joystick API.

- It uses inotify(7) to detect joystick hotplug events.

- I haven't even looked at other OSes to see if it would be possible
  to port the code.

.. EXAMPLES
.. ========

LICENSE
=======

unsaver is released under the WTFPL: Do WTF you want with this.

AUTHOR
======

unsaver was written by B. Watson <yalhcru@gmail.com>.

SEE ALSO
========

jstest(1), jscal(1), sdl-jstest(1), sdl2-jstest(2)