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Solved: Windows 10 updater stuck checking for updates

I upgraded from windows 7 to windows 10 and the automatic windows updates never worked. It always got stuck on this screen saying “checking for updates”.
checking for updates

The fix was doing a couple things. First, download this offline update tool http://download.wsusoffline.net/ and run it as described here https://www.howtogeek.com/247380/how-to-fix-windows-update-when-it-gets-stuck/ . For me, this didn’t even work. It found and applied some updates, but there were a dozen or so that could not get downloaded and installed. However, WSUS offline update did tell me which updates were still missing. Below is the output from the program.

17:00:45.06 - Listing ids of missing updates (please be patient, this will take a while)...
21:59:37.04 - Done.
Listing ids of installed updates...
Listing update files...
Warning: Update kb3127945 (id: 15d7f98f-d025-4ea5-89aa-6fbb09a41e73) not found.
Warning: Update kb3141535 (id: 1ff05279-5627-4993-a62e-4f11ee47ad31) not found.
Warning: Update kb3127890 (id: 0db092b3-c980-4ee6-9b56-54c5790bac86) not found.
Warning: Update kb3191829 (id: dbd12cba-5172-4d0c-8b53-82bcff57f799) not found.
Warning: Update kb3191827 (id: 4c304c75-1b13-4a99-b5b5-c51cef236e66) not found.
Warning: Update kb3191830 (id: bf943a21-4c4c-400b-9fda-dde26cc8867b) not found.
Warning: Update kb4017094 (id: 633a4cc1-35c9-40b9-9714-7cf158168751) not found.
Warning: Update kb3191836 (id: a32e6e50-5224-4987-ae74-24e8698aa25b) not found.
Warning: Update kb2596904 (id: 158250e3-4ef3-47ef-acf3-908145be487a) not found.
Warning: Update kb3191895 (id: 596424f1-aa0d-4d62-bb50-9368bf96df75) not found.
Warning: Update kb3191835 (id: 2366268b-d998-4c53-94cf-f69ab4823a38) not found.
Info: Skipping update kb890830 (Malicious Software Removal Tool) due to matching black list entry.

I then went to Microsoft’s website https://www.microsoft.com/en-us/download/details.aspx?id=55067 and downloaded and installed each of these one by one. Once this was done, the updater worked again and pulled down more updates. Problem Solved.


PHP floats are not created equal

I was given a bug report today and after digging into the problem I found that two floating point numbers that appeared to be equal were not.

Here is a little code and the output. At the bottom is the actual value of each.

var_dump($paymentAmount);
var_dump($amountDue);

if($paymentAmount > $amountDue) {
echo 'is greater';
} else {
echo 'equal or less';
}
printf("%.40f\n", $paymentAmount) . ' ';
printf("%.40f\n", $amountDue)

float(51.01) 
float(51.01) 
is greater
51.0099999999999980104803398717194795608521 
51.0099999999999909050529822707176208496094

PHP acknowledges the issues here under “comparing floats” http://php.net/manual/en/language.types.float.php

The PHP website provides a way to test the number for equality by limiting them to 5 decimals –

To test floating point values for equality, an upper bound on the relative error due to rounding is used. This value is known as the machine epsilon, or unit roundoff, and is the smallest acceptable difference in calculations.

$a and $b are equal to 5 digits of precision.

$a = 1.23456789;
$b = 1.23456780;
$epsilon = 0.00001;

if(abs($a-$b) < $epsilon) {
    echo "true";
}

RetroPie emulationstation not saving game progress 2

I spent part of my Saturday on this issue where I’d make progress in a game and save it within the game, but upon powering down the raspberry pi and returning, the progress would be gone. The problem is if you’re not exiting the game “cleanly”, the the emulation station will not write the game progress to the SD card, even though you’ve saved it in the game. When you configure a controller with RetroPie, it does not present you with a button combination to exit the game, which will initiate a write to the SD card. You can manually add a button combination for your controller by logging into the terminal and going to /opt/retropie/emulators/RetroArch/configs/ , then selecting your controller config, and adding the below two lines:

input_enable_hotkey_btn = 8
input_exit_emulator_btn = 9

Within the config, you’ll see each button on your controller is assigned a number. On my NES controller the “select” button was 8 and the “start” button was 9. With these lines added to the config file, I now press select and start at the same time to exit the game cleanly (which saves progress to the SD card).

Also, you can configure an automatic write to the SD card at an interval. Edit your retroarch.cfg file and uncomment the line “autosave_interval” and set it’s value to an integer representing a number of seconds. For example

autosave_interval = 5

Will save your progress to the SD card every 5 seconds.


Things I’m reading

http://www.dbasquare.com/2012/04/04/how-important-a-primary-key-can-be-for-mysql-performance/

http://coding.smashingmagazine.com/2012/06/06/all-about-unicode-utf8-character-sets/

http://misko.hevery.com/2008/07/30/top-10-things-which-make-your-code-hard-to-test/

http://www.littlehart.net/atthekeyboard/

http://www.klauskomenda.com/code/javascript-inheritance-by-example/

http://blog.scoutapp.com/articles/2009/07/31/understanding-load-averages

http://martinvalasek.com/blog/pictures-from-a-developers-life