Commands by cowholio4 (2)

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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"

check open ports without netstat or lsof

Don't like the cut command? Tired of typing awk '{print $xxx}', try this

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"

Remove lines that contain a specific pattern($1) from file($2).
The -i option in sed allows in-place editing of the input file. Replace myexpression with any regular expression. /expr/d syntax means if the expression matches then delete the line. You can reverse the functionality to keep matching lines only by using: $ sed -i -n '/myexpression/p' /path/to/file.txt

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

Pronounce an English word using Merriam-Webster.com
The original was a little bit too complicated for me. This one does not use any variables.

Command to logout all the users in one command
Logs all users out except root. I changed the grep to use a regexp in case a user's username contained the word root.

Backup your hard drive with dd
This will create an exact duplicate image of your hard drive that you can then restore by simply reversing the "if" & "of" locations. $ sudo dd if=/media/disk/backup/sda.backup of=/dev/sda Alternatively, you can use an SSH connection to do your backups: $dd if=/dev/sda | ssh user@ssh.server.com dd of=~/backup/sda.backup

Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)
Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.

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