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Google dictionary of word definitions
$ wget -qO - "http://www.google.com/dictionary/json?callback=dict_api.callbacks.id100&q=steering+wheel&sl=en&tl=en&restrict=pr,de&client=te" this does the actual google dictionary query, returns a JSON string encapsulated in some fancy tag $ sed 's/dict_api\.callbacks.id100.//' here we remove the tag beginning $ sed 's/,200,null)//' and here the tag end There are also some special characters which could cause problems with some JSON parsers, so if you get some errors, this is probably the case (sed is your friend). I laso like to trim the "webDefinitions" part, because it (sometimes) contains misleading information. $ sed 's/\,\"webDefinitions.*//' (but remember to append a "}" at the end, because the JSON string will be invalid) The output also contains links to mp3 files with pronounciation. As of now, this is only usable in the English language. If you choose other than English, you will only get webDefinitions (which are crap).

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"

RTFM function
Some commands have more information on 'info' than in the man pages

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" }

Email HTML content
Note, this works because smtp is running

Install pip with Proxy
Installs pip packages defining a proxy

View files opened by a program on startup and shutdown
Run this before you run a command in order to see what the command does as it starts. The -c flag is useful here as the PID is unknown before startup. All config files, libraries, logs, ports, etc used by the command as it starts up, (and shuts down) will be captured at 1s intervals and written to a file. Useful for debugging etc.

Start another X session in a window
You might have Xnest (older) rather than Xephyr. You can experiment with other desktops eg: startx /usr/bin/start-kde -- /usr/bin/Xephyr :2 You can start X on a remote machine (although I'd recommend vnc for anything slower than a LAN): startx /usr/bin/ssh -X gnome-session -- /usr/bin/Xephyr :2 Or just start another X session locally talking to the remote backend:

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"

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials


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