Commands by netfortius (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"

watch the previous command
If you just executed some long command, like "ps -aefww | grep -i [m]yProcess", and if you don't want to retype it or cycle backwards in history and waste time quoting it, then you can use history substitution.

display an embeded help message from bash script header
With this one liner you can easily output a standard help message using the following convention: Usage: is the start marker Stop at the last #

share internet connection with only one network interface
the below command create a alias for share your internet connection with another. $ifconfig eth0:1 192.168.0.1/24 Its obviously necessary too activate the iptables post-routing and ip forwarding, as root: $modprobe iptable_nat $iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE $echo 1 > /proc/sys/net/ipv4/ip_forward Be sure that the alias 192.168.0.0/24 is not your active real ip range

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

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

Remind yourself to leave in 15 minutes
If you spend most of your time in front of the terminal, leave is a useful reminder. Leave can have absolute form: leave 1555 reminds you to leave at 3:55PM

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"

resume download using curl

Runs previous command but replacing
Really useful for when you have a typo in a previous command. Also, arguments default to empty so if you accidentally run: $ echo "no typozs" you can correct it with $ ^z


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