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Grab IP address on machine with multiple interfaces
Instead of hard-coding in a check to scrape info from ifconfig based on a specific interface, do it in a more portable way. This works really well if you switch between wired, wireless, bluetooth or even VPN connections. You can get your current IP in a script (since it'll be something like tun0 instead of eth0 or wlan1). This uses a well known public ip address 8.8.8.8, but it doesn't actually connect to it, it just shows you the route it would take.

Convert all .flac from a folder subtree in 192Kb mp3
find . -type f -iname '*.flac' # searches from the current folder recursively for .flac audio files | # the output (a .flac audio files with relative path from ./ ) is piped to while read FILE; do FILENAME="${FILE%.*}"; flac -cd "$FILE" | lame -b 192 - "${FILENAME}.mp3"; done # for each line on the list: # FILE gets the file with .flac extension and relative path # FILENAME gets FILE without the .flac extension # run flac for that FILE with output piped to lame conversion to mp3 using 192Kb bitrate

ssh autocomplete based on ~/.ssh/config
I sue this in my .bashrc file This will also do auto-completion for scp and sftp

Number of CPU's in a system
This appears to do the same. Utility is verified to be present on Ubuntu and OpenSuse out-of-the-box.

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"

change directory to actual path instead of symlink path
If you use symlinks a lot, especially nested symlinks, this puts you back on the absolute path to command-line-fu-nirvana. (Note the backticks around pwd).

Decrypt MD5
Decrypt MD5 , replace 1cb251ec0d568de6a929b520c4aed8d1 with the MD5 string you want to decrypt

SSH connection through host in the middle

Replace spaces in filenames with underscores

Get Cisco network information
This gives you lots of nifty Cisco network information like VLAN tag, port and switch information.


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