Commands by smoky (1)

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

port scan using parallel
It takes over 5 seconds to scan a single port on a single host using nmap $ time (nmap -p 80 192.168.1.1 &> /dev/null) real 0m5.109s user 0m0.102s sys 0m0.004s It took netcat about 2.5 minutes to scan port 80 on the class C $ time (for NUM in {1..255} ; do nc -w 1 -z -v 192.168.1.${NUM} 80 ; done &> /dev/null) real 2m28.651s user 0m0.136s sys 0m0.341s Using parallel, I am able to scan port 80 on the entire class C in under 2 seconds $ time (seq 1 255 | parallel -j255 'nc -w 1 -z -v 192.168.1.{} 80' &> /dev/null) real 0m1.957s user 0m0.457s sys 0m0.994s

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"

Get Futurama quotations from slashdot.org servers

Intercept, monitor and manipulate a TCP connection.
This will handle multiple incoming connections. Also, found sed works best with -u flag (unbuffered io). Easiest way I've found to get ncat is to install nmap.

Get your mac to talk to you
Very entertaining when run on someone elses machine remotely ;)

Remove all the files except abc in the directory
This is for zsh with extended globbing.

Adjust display hardware brightness [dbus way]

Create a directory and cd into it
This creates a bash function `take` that you can call with the name of the directory as the first parameter. Add the function to ~/.bashrc to have it available anytime.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }


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