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Extract raw URLs from a file
you can also use cut instead of awk. less powerful but probably faster. ;)

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

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:

Insert a line at the top of a text file without sed or awk or bash loops
Just use '-' to use STDIN as an additional input to 'cat'

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" }

Grab mp3 files from your favorite netcasts, mp3blog, or sites that often have good mp3s
This was gotten from http://www.veen.com/jeff/archives/000573.html. The line will grab all the mp3 files on the urls listed in text file sourceurls.txt (one url per line) . A much more complete breakdown of the line can be found at the web site mentioned above.

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

take a screenshot of a webpage

vim easter egg
inside vim try: :help 42 to get the meaning of life, the universe and everything !

Do command when logged in from certain ips using ssh
Place in ~/.bashrc If you login to a ssh server from different ips, sometimes you want to do something specific for each. e.g., quickly go into screen -x session from a phone, but not your desktop.


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