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find an unused unprivileged TCP port
Some commands (such as netcat) have a port option but how can you know which ports are unused?

Find usb device
I often use it to find recently added ou removed device, or using find in /dev, or anything similar. Just run the command, plug the device, and wait to see him and only him

Ultimate current directory usage command
Based on the MrMerry one, just add some visuals to differentiate files and directories

View all new log messages in real time with color
This will show all changes in all log files under /var/log/ that are regular files and don't end with `gz` nor with a number

Show Directories in the PATH Which does NOT Exist
I often need to know of my directory in the PATH, which one DOES NOT exist. This command answers that question * This command uses only bash's built-in commands * The parentheses spawn a new sub shell to prevent the modification of the IFS (input field separator) variable in the current shell

Search commandlinefu from the CLI
html2text: http://www.mbayer.de/html2text/

Get information on your graphics card on linux (such as graphics memory size)
Loop is needed if you have more then one card.

Get IPv4 of eth0 for use with scripts
Simple and easy. No regex, no search and replace. Just clean, built-in tools.

copy timestamps of files from one location to another - useful when file contents are already synced but timestamps are wrong.
Sometimes when copying files from one place to another, the timestamps get lost. Maybe you forgot to add a flag to preserve timestamps in your copy command. You're sure the files are exactly the same in both locations, but the timestamps of the files in the new home are wrong and you need them to match the source. Using this command, you will get a shell script (/tmp/retime.sh) than you can move to the new location and just execute - it will change the timestamps on all the files and directories to their previous values. Make sure you're in the right directory when you launch it, otherwise all the touch commands will create new zero-length files with those names. Since find's output includes "." it will also change the timestamp of the current directory. Ideally rsync would be the way to handle this - since it only sends changes by default, there would be relatively little network traffic resulting. But rsync has to read the entire file contents on both sides to be sure no bytes have changed, potentially causing a huge amount of local disk I/O on each side. This could be a problem if your files are large. My approach avoids all the comparison I/O. I've seen comments that rsync with the "--size-only" and "--times" options should do this also, but it didn't seem to do what I wanted in my test. With my approach you can review/edit the output commands before running them, so you can tell exactly what will happen. The "tee" command both displays the output on the screen for your review, AND saves it to the file /tmp/retime.sh. Credit: got this idea from Stone's answer at http://serverfault.com/questions/344731/rsync-copying-over-timestamps-only?rq=1, and combined it into one line.

Dump audio from video without re-encoding.
This removes the video and subsequent file size and directly copies the audio.


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