Commands by stackoverflow128 (1)

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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"

list files recursively by size

Find jpeg images and copy them to a central location
Use if you have pictures all over the place and you want to copy them to a central location Synopsis: Find jpg files translate all file names to lowercase backup existing, don't overwrite, preserve mode ownership and timestamps copy to a central location

Add a line to a file using sudo
This is the solution to the common mistake made by sudo newbies, since $ sudo echo "foo bar" >> /path/to/some/file does NOT add to the file as root. Alternatively, $ sudo echo "foo bar" > /path/to/some/file should be replaced by $ echo "foo bar" | sudo tee /path/to/some/file And you can add a >/dev/null in the end if you're not interested in the tee stdout : $ echo "foo bar" | sudo tee -a /path/to/some/file >/dev/null

disk space email alert
put it in crontab to get an alert when / is over 89% utilization.

Encrypted archive with openssl and tar
command to decrypt: $ openssl enc -aes-256-cbc -d < secret.tar.enc | tar x Of course, don't forget to rm the original files ;) You may also want to look at the openssl docs for more options.

Sum columns from CSV column $COL

Prettify an XML file
Generated XML files often are poorly formatted. Use this command to properly indent and normalize the file in-place.

Generate Random Passwords
If you want a password length longer than 6, changing the -c6 to read -c8 will give you 8 random characters instead of 6. To end up with a line-feed, use this with echo: # echo `< /dev/urandom tr -dc _A-Z-a-z-0-9 | head -c6`

list block devices
Shows all block devices in a tree with descruptions of what they are.


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