XScreenSaver Hot Potato

xscreensaver-hot-potato.sh, for passively cooled devices with limited resources. Logs CPU temperature and active screen-saver, and depending upon configurations and logs may toggle available screen savers.

The following covers how to install this branch as a crontab job, and parameters that xscreensaver-hot-potato.sh currently responds to.

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Table of Contents

• ⬆ Top of ReadMe File

• ⚡ Quick Start

• 📜 xscreensaver-hot-potato.sh Positional Arguments

• 🗒 Notes

• 📇 Attribution

• ©️ License

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Quick Start

Git Commands

1. Make a directory for Git sources

2. Change current directory to sub-directory path

3. Clone the source

mkdir -vp "${HOME}/git/hub/rpi-curious"

cd "${HOME}/git/hub/rpi-curious"

git clone --recurse-submodules git@github.com:rpi-curious/xscreensaver-hot-potato.git

Install Commands

1. Link xscreensaver-hot-potato.sh to a PATH accessible location

2. Set ownership and executable permissions

3. Write a crontab entry

sudo ln -s "${HOME}/git/hub/rpi-curious/xscreensaver-hot-potato/xscreensaver-hot-potato.sh" '/usr/local/sbin/'

sudo chown ${USER}:${GROUPS} '/usr/local/sbin/xscreensaver-hot-potato.sh'
chmod u+x "${HOME}/git/hub/rpi-curious/xscreensaver-hot-potato/xscreensaver-hot-potato.sh"

sudo crontab -e

Example: crontab entry

*/2 * * * * su pi -c "/usr/local/sbin/xscreensaver-hot-potato.sh --max-temp-c 75 --log-path /tmp/xscreensaver-hot-potato.log --config-path /home/pi/.xscreensaver"

Example: logged hacks

# 2019-08-05 Monday 15:22:01 - Screensaver 206 ringradius - Temperature: 76
# 2019-08-05 Monday 23:22:02 - Screensaver 147 mirrorblob - Temperature: 76
# 2019-08-05 Monday 23:24:01 - Screensaver 70 bumps - Temperature: 77
# 2019-08-05 Monday 23:26:01 - Screensaver 159 interaggregate - Temperature: 76
# 2019-08-06 Tuesday 00:10:01 - Screensaver 151 popsquares - Temperature: 76

Note a more substantial example may be found under .examples/xscreensaver_hot_potato.log

Example: disable xscreensaver hacks that overheat device

xscreensaver-hot-potato.sh\
 --log-path /tmp/xscreensaver-hot-potato.log\
 --config-path ~/.xscreensaver\
 --offence-limit 3

Update

1. Change directory to repository root

2. Pull changes to source code

3. Update submodule tracked source code

cd "${HOME}/git/hub/rpi-curious/xscreensaver-hot-potato"

git pull

git submodule update --init --merge --recursive

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XScreenSaver Hot Potato API

Arguments	Type	Description
-h --help help	boolean	Prints possibly helpful message and exits
-l --license license	boolean	Prints license and exits
--max-temp-c max-temp-c	number	Max temperature in Celsius before logging of xscreensaver hack name is triggered
--max-temp-f max-temp-f	number	Max temperature in Fahrenheit before logging of xscreensaver hack name is triggered
--log-path --log	path	File path that temperature and xscreensaver hack names are logged to
--config-path --config config-path	path	File path that xscreensaver configurations are read from
--offence-limit --limit offence-limit	number	Max number any individual xscreensaver hack name may be logged, after which

Throws Parameter_Error: no configuration file found, when --config-path is not defined

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Notes

Tested on Raspberry Pi revisions 2 and 3, and may operate on other Linux based system on a chip devices.

The --help option may be used in combination with other options to check that things are assigned as expected.

Setting --max-temp-f instead of --max-temp-c will cost a bit more in computation, because conversions are required.

Until run with --offence-limit the xscreensaver-hot-potato.sh script will not disable any xscreensaver hacks.

Timing for crontab should capture 2 to 3 samples at minimum per default cycle, and xscreensaver should be configured to cycle through available hacks.

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Attribution

Resources that where helpful in building this project so far.

• Stack Overflow

  • How to get first character of variable
  • How to sort uniq and display line that appear more than x times
  • Numbering lines matching the pattern using sed

• Unix Stack Exchange

  • How to show lines after each grep match until other specific match

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License

XScreenSaver Hot Potato submodule quick start documentation
Copyright (C) 2019  S0AndS0

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as published
by the Free Software Foundation; version 3 of the License.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Affero General Public License for more details.

You should have received a copy of the GNU Affero General Public License
along with this program.  If not, see <https://www.gnu.org/licenses/>.