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Gets a random Futurama quote from /.

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"

host - DNS lookup utility
host is a simple utility for performing DNS lookups. It is normally used to convert names to IP addresses and vice versa. When no arguments or options are given, host prints a short summary of its command line arguments and options.

List detailed information about a ZIP archive
list zipfile info in long Unix ``ls -l'' format.

Lists installed kernels

Testing php configuration

Remove several files with ease
Rather than typing out all 10 files, you can use brace expansion to do the trick for you. This is useful for backup files, numbered files, or any files with a repeating pattern. Gives more control than 'rm file*' as I might want to keep others around.

A command line calculator in Perl
Once I wrote a command line calculator program in C, then I found this... and added to it a bit. For ease of use I normally use this in a tiny Perl program (which I call pc for 'Perl Calculator') #!/usr/bin/perl -w die "Usage: $0 MATHS\n" unless(@ARGV);for(@ARGV){s/x/*/g;s/v/sqrt /g;s/\^/**/g}; print eval(join('',@ARGV)),$/; It handles square roots, power, modulus: $ pc 1+2 (1 plus 2) 3 $ pc 3x4 (3 times 4) 12 $ pc 5^6 (5 to the power of 6) 15625 $ pc v 49 ( square root of 49 ) 7 $ pc 12/3 (12 divided by 3) 4 $ pc 19%4 (19 modulus 4) 3 (you can string maths together too) $ pc 10 x 10 x 10 1000 $ pc 10 + 10 + 10 / 2 25 $ pc 7 x v49 49

Get the ip registered to a domain on OpenWRT
I use this in a script on my openwrt router to check if my DynDNS needs to be updated, saves your account from being banned for blank updates.

Count items in JSON array
Pipe any JSON to jq, then count with the appropiate expression and use the | length on the array


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