Commands by narven (4)

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Using mplayer to play the audio only but suppress the video
Sometimes you only want to linsten the audio while output the video will be a waste of CPU resource and an annoying window. With option -vo null, you will enjoy the audio!

Display unique values of a column
the column number is '6'

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

Record microphone input and output to date stamped mp3 file
record audio notes or meetings requires arecord and lame run mp3gain on the resulting file to increase the volume / quality ctrl-c to stop recording

one-liner mpc track changer using dmenu
Add a [fluxbox] binding in your key file then this command provides a dmenu selector for the next track to play

gh or "grep history" - define a function gh combining history and grep to save typing
By defining a function "gh" as shown here, it saves me typing "history | grep" every time I need to search my shell history because now I only have to type "gh". A nifty time saver :-) You can also add the "gh" function definition to your .bashrc so it is defined each time you login. (updated 2015_01_29: changed from hg to gh to avoid clash with that other hg command. mnemonic: gh = grep history)

Connect to remote machine with other enconding charset

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 info about a GitHub project
In this example we search for 'vim' but vim doesn't have a project on github right now. That's ok, this command still searches for every project that has 'vim' in their description (forks, plugins, etc). To get XML or JSON output just replace 'yaml' in the url with 'xml' or 'json'.

Populate a folder with symbolic links to files listed in an m3u playlist.
This command will place symbolic links to files listed in an m3u playlist into a specified folder. Useful for uploading playlists to Google Music. prefix = The full path prefix to file entries in your .m3u file, if the file paths are relative. For example, if you have "Music/folder/song.mp3" in your list.m3u, you might want to specify "/home/username" as your prefix. list.m3u = Path to the playlist target_folder = Path to the target folder in which you would like to create symlinks

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