====== How To ======
===== links =====
<code>ln -s existingDir newDir</code>

===== alternatives =====
Choose default from different installed JREs
<code>sudo update-alternatives --config java</code>

===== Find path a program is installed in =====
<code>where program</code>

===== Shell variables =====
^Variable ^Meaning ^
|!$ |last argument of last command |
|!! |last command, e.g.  sudo !! |
|$? |exit code of last run program|



===== lame scripting tricks  =====
==== ZSHs .history under Dropbox ====
History is saved in a folder, which is sync'ed via Dropbox-Service, local .history is a symlink to that file:
  cp .history .history.bak; mv .history Dropbox/ && ln -s Dropbox/.history .history

==== short form for if constructs ====

  [[ condition ]] && doSmthIfConditionIsTrue;