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Rename files in batch

Enter parameter if empty (script becomes interactive when parameters are missing)
Can be used for command line parameters too. If you have a more complicated way of entering values (validation, GUI, ...), then write a function i.e. EnterValue() that echoes the value and then you can write: $ param=${param:-$(EnterValue)}

Find commets in jpg files.
Finds comments in jpg files, but I can't figure out how to exclude (in output) files without comments.

Download all images from a site
This recursively downloads all images from a given website to your /tmp directory. The -nH and -nd switches disable downloading of the directory structure.

Mount a disk image (dmg) file in Mac OSX
To unmount, replace "attach" with "eject"

list files recursively by size

Alias TAIL for automatic smart output
Run the alias command, then issue $ps aux | tail 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 default of 80. The default for TAIL is to output the last 10 lines, this alias changes the default to output the last x lines instead, where x is the number of lines currently displayed on your terminal - 7. The -7 is there so that the top line displayed is the command you ran that used TAIL, 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. ( http://www.askapache.com/linux/bash-power-prompt.html ) 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.

check open ports without netstat or lsof

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Exclude grep from your grepped output of ps (alias included in description)
Surround the first letter of what you are grepping with square brackets and you won't have to spawn a second instance of grep -v. You could also use an alias like this (albeit with sed): alias psgrep='ps aux | grep $(echo $1 | sed "s/^\(.\)/[\1]/g")'


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