Commands by Timothy (2)

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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.

find geographical location of an ip address
I save this to bin/iptrace and run "iptrace ipaddress" to get the Country, City and State of an ip address using the http://ipadress.com service. I add the following to my script to get a tinyurl of the map as well: URL=`lynx -dump http://www.ip-adress.com/ip_tracer/?QRY=$1|grep details|awk '{print $2}'` lynx -dump http://tinyurl.com/create.php?url=$URL|grep tinyurl|grep "19. http"|awk '{print $2}'

convert video to gif by ffmpeg and imagemagick
you can use any common video format. if you don't need to change the size of gif output, just remove `-vf scale=320:-1` btw, 320:-1 means width is 320px and height would be set automatically

Waste time for about 3 minutes
If you're a slow reader and/or you like to ponder, adjust the sleep time to be longer

stop windows update
Windows only: stops windows update and the nagging restart window. You need your admin password for this one.

Remove empty directories
It only works in zsh

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

paste one file at a time instead of in parallel
paste one file at a time instead of in parallel

Better recursive grep with pretty colors... requires ruby and gems (run: "gem install rak")

Merge *.pdf files
Merge all pdf files in the directory into one pdf file (the out.pdf file)


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