MacOS Tips

- swtich desktop screen: ctrl + arrow key

- change mouse scroll direction: system preferences -> mouse

- lock screen: ctrl+shift+reject; top left corner -> sleep;
- start screen saver: hot corner: system preferences -> mission control -> hot corner

  http://osxdaily.com/2011/01/17/lock-screen-mac/

- MS keyboard windows key maps to Apple keyboard apple command key

- go to line start/end: apple command + arrow
  - http://hints.macworld.com/article.php?story=20091113104558655

  - Shift+Home/End

- in browser, Home/End go to top/bottom of page.

- select all/copy/paste: apple command+A/C/V
- Screenshot: Shift+Command+4 (select area), Shift+Command+3 (full screen)

XScreenSaver

XScreenSaver is available on linux-based X11 systems, including major linux and BSD distributions, MacOS, iPhone, iPad and Android. It was written by Jamie Zawinski and others.

See: https://www.jwz.org/xscreensaver/
This is a very nice introduction to Writing an Xscreensaver Module using Xlib.