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Delete .svn directories and content recursively
Use carefully have rm -rf ;-)

Run a ext4 file system check and badblocks scan with progress info
Nothing fancy, just a regular filesystem scan that calls the badblocks program and shows some progress info. The used options are: -c ? check for bad sectors with badblocks program -D ? optimize directories if possible -f ? force check, even if filesystem seems clean -t ? print timing stats (use -tt for more) -y ? assume answer ?yes? to all questions -C 0 ? print progress info to stdout /dev/sdxx ? the partition to check, (e.g. /dev/sda1 for first partition on first hard disk) NOTE: Never run fsck on a mounted partition!

Place the NUM-th argument of the most recent command on the shell
After executing a command with multiple arguments like cp ./temp/test.sh ~/prog/ifdown.sh you can paste any argument of the previous command to the console, like ls -l ALT+1+. is equivalent to ls -l ./temp/test.sh ALT+0+. stands for command itself ('ls' in this case) Simple ALT+. cycles through last arguments of previous commands.

Create tar over SSH
Really useful when out of space in your current machine. You can ran this also with cat for example: $ tar zcvf - /folder/ | ssh root@192.168.0.1 "cat > /dest/folder/file.tar.gz" Or even run other command's: $ tcpdump | ssh root@10.0.0.1 "cat > /tmp/tcpdump.log"

Show the 20 most CPU/Memory hungry processes
This command will show the 20 processes using the most CPU time (hungriest at the bottom). You can see the 20 most memory intensive processes (hungriest at the bottom) by running: $ ps aux | sort +3n | tail -20 Or, run both: $ echo "CPU:" && ps aux | sort +2n | tail -20 && echo "Memory:" && ps aux | sort +3n | tail -20

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Adding Color Escape Codes to global CC array for use by echo -e
I was looking for the fastest way to create a bunch of ansi escapes for use in echo -e commands throughout a lot of my shell scripts. This is what I came up with, and I actually stick that loop command in a function and then just call that at the beginning of my scripts to not clutter the environment with these escape codes, which can wreck havok on my terminal when I'm dumping the environment. More of a cool way to store escape ansi codes in an array. You can echo them like: $ echo -e "${CC[15]}This text is black on bright green background." I usually just use with a function: $ # setup_colors - Adds colors to array CC for global use $ # 30 - Black, 31 - Red, 32 - Green, 33 - Yellow, 34 - Blue, 35 - Magenta, 36 - Blue/Green, 37 - White, 30/42 - Black on Green '30\;42' $ function setup_colors(){ declare -ax CC; for i in `seq 0 7`;do ii=$(($i+7));CC[$i]="\033[1;3${i}m";CC[$ii]="\033[0;3${i}m";done;CC[15]="\033[30;42m"; export R='\033[0;00m';export X="\033[1;37m"; }; $ export -f setup_colors CC[15] has a background of bright green which is why it is separate. R resets everything, and X is my default font of bright white. $ CC[15]="\033[30;42m"; R=$'\033[0;00m'; X=$'\033[1;37m' Those are just my favorite colors that I often use in my scripts. You can test which colors by running $ for i in $(seq 0 $((${#CC[@]} - 1))); do echo -e "${CC[$i]}[$i]\n$R"; done See: http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html for more usage.

Displays user-defined ps output and pidstat output about the top CPU or MEMory users.
It grabs the PID's top resource users with $(ps -eo pid,pmem,pcpu| sort -k 3 -r|grep -v PID|head -10) The sort -k is sorting by the third field which would be CPU. Change this to 2 and it will sort accordingly. The rest of the command is just using diff to display the output of 2 commands side-by-side (-y flag) I chose some good ones for ps. pidstat comes with the sysstat package(sar, mpstat, iostat, pidstat) so if you don't have it, you should. I might should take off the timestamp... :|

Replace all backward slashes with forward slashes
Use -i to edit file directly: sed -i 's|\\|\/|g' file

Get your external IP address
Yeah I know it's been up here a million times, but this service is a really clean and nice one. Nothing but your IP address on it. Actually I was to write something like this, and noticed this on appspot... ;)


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