====== Command Line Cheatsheet ======

===== cd =====

==== quick return to previous directory ====
  cd -

  * TIP: Using "cd -" consecutively, you can swap back and forth between two directories.

===== dpkg =====

==== backup package listing ====
  dpkg --get-selections \* > package.list

  * NOTE: Delete the "\*" from the above line, if you don't want the listing to include "purged" packages

==== restore packages (on new machine or after reinstall) ====
  dpkg --set-selections < package.list
  dselect update
  apt-get dselect-upgrade

==== place a hold on a package ====
  echo "<package> hold" | dpkg --set-selections

==== prevent long package names from getting truncated ====
  COLUMNS=160 dpkg -l

==== rebuild the "dselect" database, if something really goes wrong ====
  perl -i.bak -pe 'if (/^Status: [^\s]+ ([^\s]+) ([^\s]+)/) { $_="Status: ".($2 eq "installed" ? "install" : "purge")." $1 $2\n"}' /var/lib/dpkg/status

===== duplicity =====

[[http://www.nongnu.org/duplicity/ | Duplicity]] is a backup utility which provides incremental, encrypted, network backups using the rsync algorithm, scp/ftp/rsync as a transfer mechanism, and support for gpg.

===== git =====

==== initial git setup ====
  git config --global user.name "Tom Hoover"
  git config --global user.email tom@hisword.net
  git config --global color.diff auto
  git config --global color.status auto
  git config --global color.branch auto
  git config --global alias.ci commit
  git config --global alias.co checkout

==== start a new project ====
  cd project
  git init
  git add .
  git commit

==== create bare repository ====
  cd ..             # must be outside project directory
  git clone --bare ./project project.git
  scp -r project.git example.com:public

==== push to public repository ====
<code>
git push ssh://example.com/home/username/public/project.git

     OR, you can add the following lines to your .gitconfig file, and then "git push example.com":

[remote "example.com"]
     url = ssh://example.com/home/username/public/project.git
</code>

===== screen =====

==== print a list of active screen sessions ====
  screen -ls

==== attach to an active screen session ====
  screen -DR

===== ssh =====

==== copy public key to "authorized_keys" on remote server ====
  cat ~/.ssh/id_dsa.pub | ssh myname@mydomain.org "cat - >> .ssh/authorized_keys"

==== start mutt via ssh on remote server ====
  ssh -X <host> -l <user> xterm -e mutt