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The decline of the mobile web...

2014 Apr 8, 6:49


The decline of the mobile web http://cdixon.org/2014/04/07/the-decline-of-the-mobile-web/

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Hijacking user sessions with the Heartbleed vulnerability · Matt's Life Bytes

2014 Apr 8, 6:36

Just a quick tutorial on exploiting heartbleed for session hijacking. Is it worse to use https than http today?

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Setting up HTTP server on Windows with Node.js | JHH's blog

2014 Mar 11, 3:09PermalinkCommentstechnical windows node http

Debugging LoadLibrary Failures - Junfeng Zhang's Windows Programming Notes - Site Home - MSDN Blogs

2014 Feb 25, 2:22

How to turn on debug logging for LoadLibrary to diagnose failures. For example, see where in the dependency graph of a DLL LoadLibrary ran into issues.

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Results of the Grand C++ Error Explosion Competition

2014 Jan 28, 4:58

tgceec:

After much deliberation, the winners of the Grand C++ Error Explosion Competition are finally selected. There are two different award categories. The winners of the first category are those submissions that produced the largest error with the smallest amount of source code. These entries contain a…

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Search Art | OpenGameArt.org

2014 Jan 22, 11:40

Various folks on OpenGameArt have converted the now public domain Glitch art assets into SVG and PNG.

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Promises/A+

2013 Dec 17, 9:03

What is good and common of all JS promise designs collected as Promises/A+

Promises/A+

An open standard for sound, interoperable JavaScript promises—by implementers, for implementers.

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JavaScript Promises: There and back again - HTML5 Rocks

2013 Dec 17, 9:02

The ES6 form of Promises.

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harmony:generators [ES Wiki]

2013 Dec 17, 9:01

Adds the yield keyword enabling you to write JS code that sort of looks like C# await.

Overview

First-class coroutines, represented as objects encapsulating suspended execution contexts (i.e., function activations). Prior art: Python, Icon, Lua, Scheme, Smalltalk.

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theatlantic: Victorian Trolling: How Con Artists Spammed in a...

2013 Oct 29, 7:42


theatlantic:

Victorian Trolling: How Con Artists Spammed in a Time Before Email

The main difference between 21st-century scams and those of centuries past is one of delivery method.

Read more. [Image: Wikimedia Commons/Benjamin Breen]

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laughingsquid: I Want to Believe in RSS T-Shirt

2013 Oct 15, 9:44


laughingsquid:

I Want to Believe in RSS T-Shirt

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Video memory offer and reclaim (Windows Drivers)

2013 Sep 18, 9:41PermalinkCommentstechnical windows driver memory offer-reclaim

Moving PowerShell data into Excel

2013 Aug 15, 10:04
PowerShell nicely includes ConvertTo-CSV and ConvertFrom-CSV which allow you to serialize and deserialize your PowerShell objects to and from CSV. Unfortunately the CSV produced by ConvertTo-CSV is not easily opened by Excel which expects by default different sets of delimiters and such. Looking online you'll find folks who recommend using automation via COM to create a new Excel instance and copy over the data in that fashion. This turns out to be very slow and impractical if you have large sets of data. However you can use automation to open CSV files with not the default set of delimiters. So the following isn't the best but it gets Excel to open a CSV file produced via ConvertTo-CSV and is faster than the other options:
Param([Parameter(Mandatory=$true)][string]$Path);

$excel = New-Object -ComObject Excel.Application

$xlWindows=2
$xlDelimited=1 # 1 = delimited, 2 = fixed width
$xlTextQualifierDoubleQuote=1 # 1= doublt quote, -4142 = no delim, 2 = single quote
$consequitiveDelim = $False;
$tabDelim = $False;
$semicolonDelim = $False;
$commaDelim = $True;
$StartRow=1
$Semicolon=$True

$excel.visible=$true
$excel.workbooks.OpenText($Path,$xlWindows,$StartRow,$xlDelimited,$xlTextQualifierDoubleQuote,$consequitiveDelim,$tabDelim,$semicolonDelim, $commaDelim);
See Workbooks.OpenText documentation for more information.
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Serializing JavaScript Promise Execution

2013 Aug 10, 3:07
Occasionally I have need to run a set of unrelated promises in series, for instance an object dealing with a WinRT camera API that can only execute one async operation at a time, or an object handling postMessage message events and must resolve associated async operations in the same order it received the requests. The solution is very simply to keep track of the last promise and when adding a new promise in serial add a continuation of the last promise to execute the new promise and point the last promise at the result. I encapsulate the simple solution in a simple constructor:

    function PromiseExecutionSerializer() {
var lastPromise = WinJS.Promise.wrap(); // Start with an empty fulfilled promise.

this.addPromiseForSerializedExecution = function(promiseFunction) {
lastPromise = lastPromise.then(function () {
// Don't call directly so next promise doesn't get previous result parameter.
return promiseFunction();
});
}
}

The only thing to watch out for is to ensure you don't pass the result of a previous promise onto a subsequent promise that is unrelated.
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Kartlytics (by Deirdré Straughan)

2013 Aug 9, 7:53


Kartlytics (by Deirdré Straughan)

PermalinkCommentshumor technical Mario-kart video-game manta map-reduce cloud-computing

Considerate MessagePort Usage

2013 Aug 7, 7:14
Sharing by leezie5. Two squirrels sharing food hanging from a bird feeder. Used under Creative Commons license Attribution-NonCommercial-NoDerivs 2.0 Generic.When writing a JavaScript library that uses postMessage and the message event, I must be considerate of other JS code that will be running along side my library. I shouldn't assume I'm the only sender and receiver on a caller provided MessagePort object. This means obviously I should use addEventListener("message" rather than the onmessage property (see related What if two programs did this?). But considering the actual messages traveling over the message channel I have the issue of accidentally processing another libraries messages and having another library accidentally process my own message. I have a few options for playing nice in this regard:
Require a caller provided unique MessagePort
This solves the problem but puts a lot of work on the caller who may not notice nor follow this requirement.
Uniquely mark my messages
To ensure I'm acting upon my own messages and not messages that happen to have similar properties as my own, I place a 'type' property on my postMessage data with a value of a URN unique to me and my JS library. Usually because its easy I use a UUID URN. There's no way someone will coincidentally produce this same URN. With this I can be sure I'm not processing someone else's messages. Of course there's no way to modify my postMessage data to prevent another library from accidentally processing my messages as their own. I can only hope they take similar steps as this and see that my messages are not their own.
Use caller provided MessagePort only to upgrade to new unique MessagePort
I can also make my own unique MessagePort for which only my library will have the end points. This does still require the caller to provide an initial message channel over which I can communicate my new unique MessagePort which means I still have the problems above. However it clearly reduces the surface area of the problem since I only need once message to communicate the new MessagePort.
The best solution is likely all of the above.
Photo is Sharing by leezie5. Two squirrels sharing food hanging from a bird feeder. Used under Creative Commons license Attribution-NonCommercial-NoDerivs 2.0 Generic.
PermalinkCommentsDOM html javascript messagechannel postMessage programming technical

Inside The Tech Stack Digg Used To Replace Google Reader ⚙ Co.Labs ⚙ code + community

2013 Jul 26, 7:21PermalinkCommentstechnical digg javascript js library

URI functions in Windows Store Applications

2013 Jul 25, 1:00PermalinkCommentsc# c++ javascript technical uri windows windows-runtime windows-store

C++ constructor member initializers run in member declaration order

2013 Jul 18, 3:29PermalinkCommentsc++ development programming technical

Subtleties of postMessage

2013 Jul 15, 1:00

In IE10 and other new browsers one may create MessageChannel objects that have two MessagePorts each connected (w3c spec calls it entangled) to one another such that postMessage on one port results in the message event firing on the other. You can pass an array of ports as the last parameter to postMessage and they show up in the ports property of the message event arg.

Origin

The postMessage here is like the worker postMessage and unlike the window and iframe postMessage in that it applies no origin checking:

  1. No origin postMessage in workers and MessagePorts: postMessage(messageData, ports)
  2. Origin postMessage in windows and iframes: postMessage(messageData, targetOrigin, ports)

Unfortunately the origin isn't an optional parameter at the end to make the two postMessages have the same signature.

On the event handler side, the event arg always has an origin property. But in the no origin case it is always the empty string.

Source

There is also a source property on the message event arg which if set is an object that has a postMessage property allowing you to post back to your caller. It is set for the origin case, however, in the no origin case this property is null. This is somewhat reasonable because in the case of MessagePort and Workers there are only two endpoints so you always know the source of a message implicitly. Unlike the origin case in which any iframe or window can be calling postMessage on any other iframe or window and the caller is unknown. So not unreasonable but it would be nice if the source property was always set for consistency.

MessageChannel start

When a MessageChannel is created it has two MessagePorts, but until those ports are started they will queue up any messages they receive. Once started they will dispatch all queued messages. Ports don't have to be started to send messages.

A port may be started in two ways, either by explicitly calling the start method on the port, or by setting the onmessage callback property on the port. However, adding an event listener via addEventListener("message", does not start the port. It works this way in IE and Chrome and the spec states this as well.

The justification is that since you can have only one callback via onmessage that once set you must implicitly be ready to receive messages and its fine to start the port. As opposed to the addEventListener in which case the user agent cannot start implicitly because it doesn't know how many event listeners will be added.  I found Hixie stating this justification in geoloc meeting notes.

Links

W3C Spec

Opera introduction

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