PotatoSalad Blog

jQuery capture and transfer scroll event

2011-12-08T16:52:00.001-05:00

Here's a problem I've come up against a few times: how do you capture a scroll event and transfer that event to another object in JavaScript? Well, here's one solution:

<!DOCTYPE html>

<html>

<head>

<script class="jsbin" src="http://code.jquery.com/jquery-1.7.1.min.js"></script>

<meta charset=utf-8 />

<title>JS Bin</title>

<!--[if IE]>

<script src="http://html5shiv.googlecode.com/svn/trunk/html5.js"></script>

<![endif]-->

<script src="https://raw.github.com/brandonaaron/jquery-mousewheel/master/jquery.mousewheel.js"></script>

<style>

article, aside, figure, footer, header, hgroup, 

menu, nav, section { display: block; }

* { padding: 0; margin: 0; }

html { min-height: 1000%; }



#toolbox {

overflow: hidden;

position: fixed;

top: 100px;

left: 200px;

width: 200px;

height: 300px;

background: #ccc;

}

</style>

</head>

<body>

<div id="toolbox">

<p>

Pellentesque habitant morbi tristique senectus et netus et malesuada fames ac turpis egestas. Vestibulum tortor quam, feugiat vitae, ultricies eget, tempor sit amet, ante. Donec eu libero sit amet quam egestas semper. Aenean ultricies mi vitae est. Mauris placerat eleifend leo. Quisque sit amet est et sapien ullamcorper pharetra. Vestibulum erat wisi, condimentum sed, commodo vitae, ornare sit amet, wisi. Aenean fermentum, elit eget tincidunt condimentum, eros ipsum rutrum orci, sagittis tempus lacus enim ac dui. Donec non enim in turpis pulvinar facilisis. Ut felis. Praesent dapibus, neque id cursus faucibus, tortor neque egestas augue, eu vulputate magna eros eu erat. Aliquam erat volutpat. Nam dui mi, tincidunt quis, accumsan porttitor, facilisis luctus, metus</p>

</div>

</body>

</html>

$(document).ready(function() {



var toolbox = $('#toolbox'),

height = toolbox.height(),

scrollHeight = toolbox.get(0).scrollHeight;



toolbox.on('mousewheel', function(event, delta) {

if ((toolbox.scrollTop() === (toolbox.get(0).scrollHeight - toolbox.height()) &&

delta < 0) || (toolbox.scrollTop() === 0 && delta > 0)) {

return event.preventDefault();

}

});



$(document).on('scroll', function(event) {



var pageX = $(this).scrollLeft(),

pageY = $(this).scrollTop(),

toolX = toolbox.scrollLeft(),

toolY = toolbox.scrollTop(),

ratio = (toolbox.get(0).scrollHeight - toolbox.height()) / $(this).height(),

pageRelX = pageX / ratio,

pageRelY = pageY / ratio,

toolRelX = ratio * pageX,

toolRelY = ratio * pageY,

prevX = $(this).data('prevScrollLeft') || 0,

prevY = $(this).data('prevScrollTop')  || 0;



$(this).data('prevScrollLeft', pageX);

$(this).data('prevScrollTop',  pageY);



console.log("other ratio: (x: %f, y: %f)",

prevX / pageX,

prevY / pageY);



console.log("ratio: %f", ratio);

console.log("page[%dx%d]: (x: %d, y: %d) => (x: %d, y: %d)",

$(this).width(),

$(this).height(),

pageX,

pageY,

pageRelX,

pageRelY);

console.log("tool[%dx%d]: (x: %d, y: %d) => (x: %d, y: %d)",

toolbox.width(),

toolbox.height(),

toolX,

toolY,

toolRelX, 

toolRelY);

//$(this).scrollLeft(pageRelX);

//$(this).scrollTop(pageRelY);

toolbox.scrollLeft(toolRelX);

toolbox.scrollTop(toolRelY);

});



});

You can view an example of this here: http://jsbin.com/evubud/2

Best UNIX Shell tools

2011-12-06T15:51:00.001-05:00

I stumbled across this while looking up how to install pgrep on Mac OS X, a gist entitled, “Best UNIX Shell tools”...



# Best UNIX Shell tools #



These are a list of usages of shell commands I can't live without on UNIX-based systems.



## Install ##



### Mac OS X ###



Using Homebrew (yes, I am opinionated) you can install the following tools with the following packages:



    brew install proctools # to install pgrep, pkill, etc.

    brew install pstree # to be able to use pstree

    brew install vnstat # to be able to use vnstat

    brew install ncdu # to use ncdu

    brew install ipcalc # to use the almighty ipcalc

    brew install htop # to use htop

    brew install ack # to use the awesome ack

    brew install lsof # to use the amazing lsof



### Fedora/Red Hat/CentOS ###



Using YUM you can install the tools with the following RPM packages:



    yum install proctools # same as brew package

    yum install psmisc # for pstree

    yum install vnstat # for vnstat

    yum install ncdu # for ncdu

    yum install initscripts # for ipcalc - should already have this, I think?

    yum install htop # for htop

    yum install ack # for ack

    yum install lsof # for lsof



### Ubuntu/Debian APT ###



Using APT you can install the tools with the following RPM packages:



    apt-get install procps

    apt-get install psmisc

    apt-get install vnstat

    apt-get install ncdu

    apt-get install ipcalc

    apt-get install htop

    apt-get install ack

    apt-get install lsof

#!/usr/bin/env bash



ncdu # launches ncurses version of `du` that makes it nice to navigate around in



pgrep -L beam.smp # lists all Erlang processes

pkill ruby # kills all Ruby processes



fc # opens previous command in your $EDITOR then after editing line, will execute on editor quit

fc pgrep # opens last command starting with pgrep in $EDITOR



lsof -iTCP # show current TCP connections

lsof -i :8080 # show current connections on port 8080

lsof -i@your.remote.host # show all connections to/from your.remote.host

lsof -u `whoami` # show all your user's connections

lsof -c beam.smp # show all connections for Erlang nodes

lsof /path/to/file # show all OS processes using or pointing to that file path

lsof -p 4830 # show all connections for a specific PID (4830)

lsof -a -u USER -c beam.smp # show all connections for Erlang nodes running as USER



/etc/init.d/nginx stop

sudo !! # runs previous command but prefixes sudo before it (can use anything instead of sudo, the key is !!)

^stop^start # reruns previous command but substitutes stop for start



vim /really/long/path/to/file.crap

ghc !$ # use argument from previous command using !$...can prefix with anything, just an example usage with ghc.



vnstat -l 1 -i eth0 # show live transfer counters for interface eth0



ack "text/pattern to search for" # equivalent to a faster fgrep for all files in current directory or under (recursively)



htop # shows colourful version of top with CPU ASCII art display :)



ipcalc 192.168.0.1/32 # displays information about resulting broadcast network, very very useful!



pstree -u USER # show process tree for all procs running as USER

pstree -p PID -l 2 # show process tree for all procs under PID at 2 levels deep





echo "Enjoy and heckle me on Twitter @SusanPotter if you want to tell me what commands you can't live without not in this usage script! :)"

I've used the majority of these utilities in the past, but I've never seen one location that shows them all together with a few simple usage examples to jog your memory. Great for remembering how to use pgrep, pkill, pstree, vnstat, ncdu, ipcalc, htop, ack, and lsof.

Rails 3 Routing with Custom Resource Globs

2011-08-17T15:58:00.005-04:00

I ran into a convenience problem while working on a recent project:

By default, when you use resources :categories in your config/routes.rb file, you get the following routes set up:

resources :categories



## equivalent to:



get    '/categories(.:format)'          => 'categories#index',  :as => :categories

post   '/categories(.:format)'          => 'categories#create'

get    '/categories/new(.:format)'      => 'categories#new',    :as => :new_category

get    '/categories/:id/edit(.:format)' => 'categories#edit',   :as => :edit_category

get    '/categories/:id(.:format)'      => 'categories#show',   :as => :category

put    '/categories/:id(.:format)'      => 'categories#update'

delete '/categories/:id(.:format)'      => 'categories#destroy'

This enables URL's like http://host/categories/4e382a079a86653864000002, but I wanted to be able to have urls like http://host/categories/category/sub_category/sub_sub_category.

After searching around a bit, I stumbled across a line in the Rails Guide on route globbing about using the :constraint option. Here's an example of to get the desired result:

resources :categories, :constraints => { :id => /.+?/ }



## equivalent to:



get    '/categories(.:format)'          => 'categories#index',  :as => :categories

post   '/categories(.:format)'          => 'categories#create'

get    '/categories/new(.:format)'      => 'categories#new',    :as => :new_category

get    '/categories/*id/edit(.:format)' => 'categories#edit',   :as => :edit_category

get    '/categories/*id(.:format)'      => 'categories#show',   :as => :category

put    '/categories/*id(.:format)'      => 'categories#update'

delete '/categories/*id(.:format)'      => 'categories#destroy'

Automatic paging with ack and rak (git style)

2008-04-26T08:22:00.006-04:00

After reading Git-Style Automatic Paging in Ruby, I wanted to try it out on my new favorite command line toy: ack.

Getting ack to work is as simple as adding the following to your ~/.ackrc.

# Always color, even if piping to a filter
--color

# Use "less -r" as my pager
--pager=LESS=FSRX less -r

rak is very similar to ack, only written in Ruby. To see some examples of using rak, check out Getting to Know a Gem: Rak.

rak doesn't support paging by default, so I'd have to do a really quick hack to get things to work. Luckily, rak is hosted on git at git://git.donttreadonme.co.uk/rak, so I forked it over at GitHub and copied the run_pager method from the cheat project.

The results can be seen over at http://github.com/PotatoSalad/rak. I wanted to try out github's new gem building feature, so I included a gemspec file in my changes. If you've got rubygems installed, just run...

gem sources -a http://gems.github.com/ (you only need to run this once)
sudo gem install PotatoSalad-rak

(see gems.github.com for more information)

Finally, if you'd like to see my changes/make your own, grab a copy of my repository with git clone git://github.com/PotatoSalad/rak.git

Simple Gmail Phishing Filter

2007-07-31T16:56:00.001-04:00

After I noticed the tauntingly large number of messages sitting comfortably in my Spam folder the other day, I went about the routine of performing the "Delete all spam messages now" that many Gmail users are accustomed to. I then checked my inbox to find that 26 of my 32 unread e-mails were phishing attempts. Not bad, Gmail's spam filtering system managed to keep around 98% of the Spam out of my inbox, but the 2% of messages that continue to seep through all have one thing in common: YOUR EMAIL HAS WON!!! UK LOTTERY WINNER!!!

I seem to be very lucky in the United Kingdom, I win their lottery at least 7 times a day. Perhaps I'm living on the wrong side of the Atlantic Ocean. These "lottery" or "jackpot" phishing attempts are really the only type of message that consistently gets passed Gmail's filtering system, aside from the occasional Japanese or Russian one (I have no idea if they're phishing attempts, but I do recognize things like ¥5000000 and "SSN PLZ").

So, I came up with a so-far highly effective and simple filter solution that has been able to catch that remaining 2% that keeps slipping through:

Matches: (Lottery OR Jackpot OR UK OR "United Kingdom")
Do this: Skip Inbox, Apply label "Phishing"

Now all I have to do is take a quick glance at the messages labeled as "Phishing" and see if a valid e-mail accidentally got flagged by the filter.

I8kfanGUI for Mac OS X v0.2 with Dual Fan Support

2007-06-15T08:38:00.000-04:00

This is a very, very quick and dirty update to allow for secondary fan control. If your laptop only has one fan, there really is no reason to upgrade.

Please note that I have no way of testing if secondary fan support actually works, so please let me know if there are any problems with it. I'm basing it off of other code out there. I still need to clean up the code and allow for simple things like saving preferences and such. I may end up making this a system preferences panel.

So, without further delay, grab the new release from the I8kfan project downloads page, or from right here:

I8kfanGUI_v0.2.dmg (I8kfanGUI v0.2 and I8kfan.kext v1.0.0d1 including sources)
I8kfanGUI_v0.2-source.tar.bz2 (I8kfanGUI Xcode project)

Note: I mentioned this in my last post, but older model laptops (Inspiron 1100, 5100, etc.) or any model that does not have Enhanced SpeedStep (CPU flag EST) still require AppleIntelCPUPowerManagement.kext. Many sites recommend deleting this file, but your older laptop's temperature will skyrocket from 35°C to 65°C.

Developers: You can also grab the source from the I8kfan project subversion repository:

I8kfan.kext
- svn co http://i8kfan.googlecode.com/svn/driver/tags/I8kfan_v1.0.0d1/
- svn co http://i8kfan.googlecode.com/svn/driver/trunk/
I8kfanGUI
- svn co http://i8kfan.googlecode.com/svn/gui/tags/I8kfanGUI_v0.2/
- svn co http://i8kfan.googlecode.com/svn/gui/trunk/

I8kfanGUI for Mac OS X

2007-05-12T22:24:00.001-04:00

Update (June 15, 2007): I8kfanGUI v0.2 with dual fan support has been released.
As a continuation of my Dell fan control problem on my Inspiron 5100 notebook, I completely rewrote the IOI8KFan.kext driver and renamed it to simply I8kfan.kext. In addition, I wrote a pretty little application to monitor the CPU temperature after the manner of the original I8kfanGUI for Windows.
The driver is written in C with inline assembly and uses the BSD sysctl system because I couldn't figure out how to use IOKit to save my life. I broke just about every "good practice" rule out there while writing this driver.
The I8kfanGUI application itself was originally going to be a daemon that simply ran in the background to control the temperature (if you look at the source, you can see my scrapped daemon), but I ended up with completely ripping off the Windows version of I8kfanGUI. This is my first Cocoa application and yes, I know it is poorly written.
It comes complete with an awesome status bar item that shows the CPU's current temperature. The unoriginal idea came from the Windows version of I8kfanGUI, but whatever. I wrote this mostly for myself anyway.
Here are a few screenshots of my awesome app in action:

Sweet. I made an i8kfan project to both host my code and to hopefully have a central place for future developments with the i8k driver on other platforms.
You can grab the source and binaries at the project downloads page or from right here:

I8kfanGUI_v0.1.dmg (I8kfanGUI and I8kfan.kext driver)
I8kfanGUI_v0.1-source.zip (I8kfanGUI Xcode project)
I8kfan_v1.0.0d1-source.zip (I8kfan.kext Xcode project)

Note: Most people won't have to mess with this because they're on later model notebooks, but my Inspiron 5100 does not have Enhanced SpeedStep (CPU flag EST) and at this time still requires AppleIntelCPUPowerManagement.kext that most sites out there encourage you to delete. My laptop went from running at around 65°C to 55°C and by using my app, it now hovers around 38°C to 43°C.

Dell Fan Control - I8kfan for Mac OS X

2007-05-05T12:52:00.000-04:00

Update (June 15, 2007): I8kfanGUI v0.2 with dual fan support has been released.

Update (May 12, 2007): Updated version of I8kfan driver including a GUI called I8kfanGUI.

My old Dell Inspiron 5100 is notorious for overheating due to a poorly designed fan system. On Windows, I use a wonderful utility called I8kfanGUI which allows me to set temperature thresholds and control the speed of the fan to prevent overheating. On Mac OS X, however, there is no such utility.

After several hours of staring blankly at Apple's I/O Kit documentation and scrutinizing the available Linux and FreeBSD code, I finally came up with a kernel extension that sucks, but it works.

I wrote up a topic over at InsanelyMac in case anyone else wants to mess around with the code. It needs to be cleaned up, but I'm just glad that I can now at least manually kick the fan into high speed whenever the laptop begins to overheat.

You can grab the kext and source from the forum post or you can grab them right here:

IOI8KFan.zip (IOI8KFan.kext)
IOI8KFan-source.zip (IOI8KFan Xcode project)

portaPuTTY 0.60 (svn+7489)

2007-05-03T12:45:00.000-04:00

Rebuilt portaPuTTY using the PuTTY 0.60 source. It's mostly bug fixes, but you can check out their change log. Stuff like "You can now store a host name in the Default Settings" could prove useful with the portable version.

I wrote up some portaPuTTY build instructions in case anyone else is feeling adventurous.

You can grab the release from the downloads page or from right here:

Binaries
- portaPuTTY_0.60+20070503.zip
Source
- portaPuTTY_0.60-source.tar.bz2
- portaPuTTY_0.60-source.zip
- Subversion:
  svn co http://portaputty.googlecode.com/svn/tags/portaputty_0.60

And, of course, you can always grab the latest development snapshot from the trunk:
svn co http://portaputty.googlecode.com/svn/trunk

portaPuTTY Project and Truly Portable PuTTY 0.59 (svn+7147)

2007-05-02T18:01:00.000-04:00

Since the source code for my version of portable PuTTY was starting to become a bigger and bigger job to keep track of, I set up a project over at Google Code with the (stolen) name of portaPuTTY. This should also solve the problem with the free download sites going under. The original guy to use the name (I think) is Socialist Sushi, but his has not been updated in a year or so. If anyone has any problems with my unoriginal choice for a name, just leave a comment.

This is the latest version of PuTTY that I have built. Unlike my last releases, this one is actually based on the final 0.59 version of PuTTY. I realize that the guys over at PuTTY have recently released version 0.60, but I have not had time to update the build yet.

Just head over to the portaPuTTY Project Page for the binaries and sources. Or you can grab them here:

Binaries
- portaPuTTY_0.59+20070206.zip
Sources
- portaPuTTY_0.59-source.tar.bz2
- portaPuTTY_0.59-source.zip
- You can also get the source from the subversion repository:
  svn co http://portaputty.googlecode.com/svn/tags/portaputty_0.59

The latest development snapshot is available in the subversion repository:
svn co http://portaputty.googlecode.com/svn/trunk

Exaile 0.2.9b on Windows

2007-01-30T12:20:00.002-05:00

If you've ever used Amarok, you probably know why so many people love it so much. My only problem with Amarok is their lack of support for Gnome (can't blame 'em, it was written in Qt for KDE).

That's where the Exaile project comes in. It's still a little rough and isn't as mature as Amarok, but it's making progress. I use it all the time when I'm on my Linux desktop, but sometimes I'm forced to use Windows. There are plenty of fine music players out there, but none that I can find are as extensive as Amarok (and eventually Exaile) are.

Since Exaile is written in Python and written in GTK+, I figured getting it to run on Windows wouldn't be too difficult. I finally got it to work (barely), but IANAPP. Maybe someone will come along and continue what I started, maybe I'll finally learn Python, or maybe someone in the Exaile project will allow extensions using Ruby.

Here are the screenshots for Exaile Win32 0.2.9b:

Truly Portable PuTTY 0.58+svn r6860

2006-10-07T18:16:00.000-04:00

Well, my last portable PuTTY worked fine and all until I actually tried to use it in conjunction with Xming. I didn't build it with the ability to use the settings directory based on the location of the executable instead of the launch point. If that makes any sense. Anyway, PuTTY, Plink, and Pageant work great now (the three main programs that I use). I posted a comment on the portaPuTTY site and it was up for a day or so, but I guess the author of the site decided that my changes aren't of any use (although the program actually works like it should). Oh well. Get it from one of the places I uploaded it to:

Binaries

portaputty_20061007.rar 1.02 MB (rarhost)
portaputty_20061007.zip 1.18 MB (rapidshare)
portaputty_20061007.zip 1.18 MB (megaupload)

Source

portaputty-source_20061007.rar 926 KB (rarhost)
portaputty-source_20061007.zip 1.11 MB (rapidshare)

portaputty-source_20061007.zip 1.11 MB (megaupload)

Here are the things I changed:

PuTTY now looks for the settings files under the same directory as the executable.
Now it's truly portable (copy and move the executables and configuration around at will).

Portable PuTTY 0.58+svn r6860

2006-09-25T20:45:00.000-04:00

I rebuilt a portable version of PuTTY today with a few changes that I needed in order to get it working the way I wanted. My build is based on the PuTTY svn repository revision 6860, but my changes could easily be applied to version 0.58. My changes are based on what I found at the portaPuTTY site. Get it from one of the places I uploaded it to:

Binaries

portaputty_20060925.rar 1.02 MB (rarhost)
portaputty_20060925.zip 1.18 MB (rapidshare)
portaputty_20060925.zip 1.18 MB (megaupload)

Source

portaputty-source_20060925.rar 1.83 MB (rarhost)
portaputty-source_20060925.zip 2.27 MB (rapidshare)

portaputty-source_20060925.zip 2.27 MB (megaupload)

I built this sucker with Visual C++ 2005 Express Edition with Microsoft's Platform SDK for Windows Server 2003 R2. I haven't thoroughly tested this thing, but it seems to work well so far. Here are the things I changed:

Pageant reads saved sessions from the files instead of from the registry (this was my main reason for building my own).
Fonts should work perfectly now. I know some people reported it as being patched, but I was still having problems with it.
Reading and writing to the randomseed file works correctly now (I was having problems with PuTTY crashing).
Used the dirent implementation from here.
Updated the Recipe file for generating the Makefiles with dirent and pageant with winstore (to allow for reading from the configuration files).