Commands by shrimphead (1)

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Comma insertions
Insert a comma where necessary when counting large numbers. I needed to separate huge amounts of packets and after 12+ hours of looking in a terminal, I wanted it in readable form.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Git Tree Command with color and tag/branch name

Extract content between the first " and the last " double quotes
Thanks to this user: https://stackoverflow.com/a/35636373/2394635

execute your commands hiding secret bits from history records
$ wget --user=username --password="$password" http://example.org/ Instead of hiding commands entirely from history, I prefer to use "read" to put the password into a variable, and then use that variable in the commands instead of the password. Without the "-e" and "-s" it should work in any bourne-type shell, but the -s is what makes sure the password doesn't get echoed to the screen at all. (-e makes editing work a bit better)

The wisdom of Cave Johnson
There's been a similar Futurama thing around for a while, which grabs a quote from the /. headers [curl -Ism3 slashdot.org | egrep "^X-(F|B|L)" | cut -d \- -f 2- | fmt -w $(tput cols)]. Same deal, but more likely to stop working when someone forgets to pay the bill on the domain. Until then: Cave Johnson!

Batch Convert SVG to PNG (in parallel)
Use GNU Parallel: short, easy to read, and will run one job per core.

Google Spell Checker
http://immike.net/blog/2007/04/07/hacking-google-spell-checker-for-fun-and-profit/

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"

scp a good script from host A which has no public access to host C, but with a hop by host B
middlehost allows ssh access from where you are but not securehost. Use nice ssh piping to simulate scp through A => B => C setting up the shell function if left as an exercise for the reader. ;-) Agent forwarding should avoid password typing.

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