Ryan Chapin's Website

Windows tends to store a ton of temporary files that, over time, tend to fill up your hard drive.

There
are a number of places to look for these files and a couple of things
you can do to periodically purge your system of files you don’t need.

First, right-click on your C drive and select "Properties".  Then click on the "Disk Cleanup" button on the main tab.

You can also look in C:\Documents and Settings\Administrator\Local Settings\Temp

And look for bloated temp folders in here.

For all of you out there who use vi on a regular basis . . . I recently needed to do a search and replace on a large document and needed to key off of the new line characters in the document.

After a bit of searching here’s what I found:

If you need to do something like, search for all new lines and add the new line plus "foo" do the following:

:1,%s/\n/^Mfoo/g

You get the ^M character by pressing ctrl-v and then hitting enter.

Anyone who has tried to W3C validate a page with the default output from Flash knows you get a slew of errors.

Here’s a great article on modifying your <object> and <embed> tags so that your pages will validate.

Flash Satay: Embedding Flash While Supporting Standards by Drew McLellan

Here’s a quick example that you can run with that includes the markup for a transparent background:

<object type="application/x-shockwave-flash" width="368" height="201" data="icms_art/nbir5.hdr.anim.swf">
<param name="allowScriptAccess" value="sameDomain" />
<param name="allowFullScreen" value="false" />
<param name="movie" value="icms_art/nbir5.hdr.anim.swf" />
<param name="quality" value="high" />
<param name="wmode" value="transparent" />
</object>

Let’s say you have a disk that you want to put in an external USB enclosure, mount and read some files.  What if it’s a boot disk that uses LVM?  What if you have two LVM groups with the same name?

Here’s a quick how-to on mounting just this type of LVM volumes from a USB disk.

When you first attach your disk in it’s USB enclosure you should be able to see which device it is associated with by looking at /var/log/messages.  In my case, it was assigned to /dev/sdc

When you run an fdisk command on the drive you’ll get something like:

Disk /dev/sdc: 80.0 GB, 80000000000 bytes
255 heads, 63 sectors/track, 9726 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0xd0f4738c

   Device Boot      Start         End      Blocks   Id  System
/dev/sdc1   *           1          13      104391   83  Linux
/dev/sdc2              14        9726    78019672+  8e  Linux LVM

The problem is a bit more complicated when both your existing OS and the disk that you want to mount have the same name for their logical volume.

Do a pvscan and you’ll be able to see the names of the logical volumes on the two disks.

# pvscan
  PV /dev/sdc2   VG VolGroup00   lvm2 [74.38 GB / 0    free]
  PV /dev/sda2   VG VolGroup00   lvm2 [74.31 GB / 32.00 MB free]

In this case, you will need to rename the volume group on the disk that you want to mount via the USB enclosure.  You’ll need to do one of two things:

• Shutdown your existing computer, disconnect the drives from it, attach the erstwhile USB mounted disk and fire it up with some sort of boot/rescue CD
• Put the disk in another box, and fire up with the aforementioned boot/rescue CD

I had an extra chassis lying around that I could use so instead of mucking around in my machine, I just used it.  I also used the Fedora Core 8 installation DVD, but you should be able to use any type of Linux rescue disk that contains the lvm binaries.

So once you’ve got your hardware all set up, boot using the rescue disk.  In this case, using the FC 8 install disk, when you get to the prompt where it asks if you want to search for and mount an exsiting partition/installation, select "Skip".

You’ll now be on the command line.  Keep in mind that in rescue mode, all lvm commands need to be preceded with "lvm".

Do a search/scan for your logical volumes with one of the following commands:

# lvm vgscan
# lvm lvscan
# lvm pvscan

# vgscan
Reading all physical volumes.  This may take a while…
Found volume group "VolGroup00" using metadata type lvm2

Then rename your volume group:

# lvm vgrename VolGroup00 VolGroup01

You could name it anything that you want, that’s just what I happened to use.

Shutdown your machine and put the newly renamed volume group disk back in it’s USB enclosure, attach to your computer and fire it up.

A vgscan should display the following:

# vgscan
Reading all physical volumes.  This may take a while…
Found volume group "VolGroup01" using metadata type lvm2
Found volume group "VolGroup00" using metadata type lvm2

Activate the volume:

# vgchange -a y /dev/VolGroup01
  2 logical volume(s) in volume group "VolGroup01" now active

Mount the volume group

# mount /dev/mapper/VolGroup01-LogVol00 /mnt

Done!

You may or may not have to include the "mapper/" entry in the path, check with your distro to see how it deals with paths to volume groups.  All I had to do was "tab" once I typed /dev/mapper/VolGroup01 and it scrolled through the available logical volumes in the group.

I’ve got a client that needs a site with a simple navigational program to be hosted under IIS with ASP.NET.

So, I put together IIS on a VMWare XP install and here’s the quick how-to:
1. Go to Add/Remove programs
2. Put the WinXP Pro install CD in the machine.
3. Click on Add/Remove Windows Components and click on the check box next to Internet Information Services (IIS)
4. After installation you should be able to open up a browser and type "localhost" and get the default welcome page.
5. If you get either a You are not authorized to view this page" or a user name and password prompt, make sure that the user account with which you are currently logged in has administrator rights and that you have a password set for that account.
6. Install .NET
7. Register .NET with IIS

Open a CMD window, change dir to
C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727(or whatever other version you are registering)

Run the following commands in sequence:
aspnet_regiis -i
aspnet_regiis -s W3SVC/
8. Make sure to include the .aspx extension on your files and you should be all set to start developing .NET applications.

Let’s say you are building an application and want to be able to dynamically instantiate new objects in AS 3.0 (Flash CS3)?

Read on for the answer . . .

The syntax for doing this has drastically changed from AS 2.0, however there is still one gotcha that remains the same.

In my case, I’m not only dynamically instantiating class names, but also their reference names.

Here’s how I figured out how to do it:

// Import the getDefinitionByName util and your class
import flash.utils.getDefinitionByName;
import com.example:ExampleClass;

// Create a variable to store a reference to your new class
var classReference:ExampleClass;

// Create a class object and use getDefinitionByName to specify the name of the class you are instantiating.
var class_tempClass:Class = Class(getDefinitionByName("com.example:ExampleClass"));
classReference = new class_tempClass();

This works great.  However, what if you don’t know what classes you’ll be instantiating and want to be able to leave that open at runtime?  This is where it’s the same in 2.0.  If you don’t include the reference to the class at compile time (var classReference:ExampleClass; ) you cannot dynamically instantiate this class, regardless of whether or not it is in your class path.

As a result, you are left with having to decide which classes you might want to instantiate at runtime and somewhere in your code, include a reference to each class such that it’s included at compile time.

Another AS 3.0 programmer indicated that it might be possible to dynamically load a swf that includes a reference to that class, but you would have to load and make sure that that swf has initialized before attempting to instantiate the object.

Maybe a way to go about it is to keep a library of swf files that have the same name as the class that you want to instantiate and write a utility that will dynamically instantiate objects.  The first thing it would do is load a swf with a reference to the class, then it would instantiate the object, returning to the calling code a reference to the newly created instance.

I think I’ll give that a try and then post and update to this thread with my findings.