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Alias HEAD for automatic smart output
Run the alias command, then issue $ps aux | head and resize your terminal window (putty/console/hyperterm/xterm/etc) then issue the same command and you'll understand. $ ${LINES:-`tput lines 2>/dev/null||echo -n 12`} Insructs the shell that if LINES is not set or null to use the output from `tput lines` ( ncurses based terminal access ) to get the number of lines in your terminal. But furthermore, in case that doesn't work either, it will default to using the deafault of 12 (-2 = 10). The default for HEAD is to output the first 10 lines, this alias changes the default to output the first x lines instead, where x is the number of lines currently displayed on your terminal - 2. The -2 is there so that the top line displayed is the command you ran that used HEAD, ie the prompt. Depending on whether your PS1 and/or PROMPT_COMMAND output more than 1 line (mine is 3) you will want to increase from -2. So with my prompt being the following, I need -7, or - 5 if I only want to display the commandline at the top. ( https://www.askapache.com/linux/bash-power-prompt/ ) 275MB/748MB [7995:7993 - 0:186] 06:26:49 Thu Apr 08 [askapache@n1-backbone5:/dev/pts/0 +1] ~ $ In most shells the LINES variable is created automatically at login and updated when the terminal is resized (28 linux, 23/20 others for SIGWINCH) to contain the number of vertical lines that can fit in your terminal window. Because the alias doesn't hard-code the current LINES but relys on the $LINES variable, this is a dynamic alias that will always work on a tty device.

Show memory usage of all docker / lxc containers

Pimp your less
# s = combine multiple lines of whitespace into 1 # x4 = set the tabstop to 4 instead of 8 # F = Exit if the output fits on 1 screen. This is similar to git diff # R = Raw control chars. This allows you to pipe colordiff straight to less. ie: alias sdi="svn diff | colordiff | less" # S = Chop off long lines # X = Dont send termcap init and deinit scrings to the terminal

view http traffic

Simple complete system backup excluding files or directories
You can exclude more system folders or individual files which are not necessary for the backup and can be recreated after the restore procedure, like /lost+found, /mnt, /media, /tmp, /usr ... Restoring the above backup procedure is as simple as becoming root and typing: $ tar zxpf backup.tgz -C / You can extract any file or directory out of the backup.tgz file for recovery, for instance, if you have a corrupt or mis-configured fstab file, you could simply issue the command: $ tar zxpf backup.tgz /ect/fstab -C / Other options: v add verbose option to see files processed A far safer solution is to restore the desired files under a different directory, and then compare, move, or update the files to their original locations afterward.

Email a file to yourself
This works on Solaris 10.

Fix the vi zsh bindings on ubuntu
Use sed to comment out any up/down bindings in zsh

pushd rotates the stack so that the second directory comes at the top.
'pushd +1' is equivalent to 'pushd'. Can be 'pushd +3' or more generaly 'pushd +N'. Can also be 'pushd -N'. More description in 'man bash'.

creeate file named after actual date
Create a file with actual date as filename

Don't save commands in bash history (only for current session)
Only from a remote machine: Only access to the server will be logged, but not the command. The same way, you can run any command without loggin it to history. ssh user@localhost will be registered in the history as well, and it's not usable.


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