Essential Windows PowerShell Commandlets

Previously, we learned the basic commands: help and gal. I suppose now it's time to properly refer to these "commands" as commandlets or cmdlets following PowerShell's own set of terminologies. But just to note that whenever both commands and commandlets, I use them interchangeably for the same semantic meaning. Call me stubborn. Call it bad habit. But they really are all just commands to me. In any case, although I think of all of the commandlets simply as commands, we should still mentally note at the back of our mind that for "data-typing" purposes, PowerShell truly types these items or commands as Cmdlet.

Our first essential command after learning the basics is Get-Command

Get-Command

Get-Command outputs all of the available commands in PowerShell in a clean PowerShell installation. These are the commands that we really will use as the building blocks for writing PowerShell scripts. Through a process of trial and errors, let us try to see if we can perform the obligatory, introductory of any programming lesson: print the string "Hello World!" on screen (I promise I'll keep the trial and errors to an abridged version).

1. Type-in Get-Command at the prompt
2. Observe the output and see if any of the command contains descriptions that indicates it is a command for printing anything on-screen by using guess-words such as: "Print", "echo", "Write", "Response", or any other words from whatever your other experience may have been.
3. If nothing on-screen indicates as such, then you'll want to type in help [Cmdlet name] at the prompt to read the details one-by-one. Hey at least that's how I started learning PowerShell, by reading documentation as well as by trial and errors.

But, let's use my experience, shall we? Let's just type in the following simple command, and we'll simply get the result we want just as we'd see in Listing 1.

Listing 1: PS C:\Users\antonius> gcm | where {$_.definition -match ".*print*"} CommandType Name Definition ----------- ---- ---------- Cmdlet Out-Printer Out-Printer [[-Name] <string>] [-InputObject <psobje... ps c:\Users\antonius> gcm | where {$_.definition -match ".*echo*"} CommandType Name Definition ----------- ---- ---------- Cmdlet Set-AuthenticodeSignature Set-AuthenticodeSignature [-FilePath] <string []> [-C... PS C:\Users\antonius> gcm | where {$_.definition -match ".*write*"} CommandType Name Definition ----------- ---- ---------- Cmdlet Write-Debug Write-Debug [-Message] <string> [-Verbose] [-Debug] ... Cmdlet Write-Error Write-Error [-Message] <string> [-Category <errorcat... cmdlet write-host write-host [[-Object] ><object>] [-NoNewline] [-Separ... Cmdlet Write-Output Write-Output [-InputObject] <psobject []> [-Verbose] ... Cmdlet Write-Progress Write-Progress [-Activity] <string> [-Status] <strin... cmdlet write-verbose write-verbose [-Message] ><string> [-Verbose] [-Debug... Cmdlet Write-Warning Write-Warning [-Message] <string> [-Verbose] [-Debug...

From these output we can sort of guess which command we can use, but if in case we're still in doubt we could always do help write-debug, help write-error, etc. Soon after we go through this we'll find the command we want to use is Write-Output.

That's a rather "long" command to type, though. Let's try to see if there's a shorter version of it. For this purpose, let's try what's on Listing 2.

Listing 2: PS C:\Users\antonius> gal | where {$_.definition -match "Write-Output"} CommandType Name Definition ----------- ---- ---------- Alias write Write-Output Alias echo Write-Output

Now that we found what we want, we can try either command aliases just as in Listing 3

Listing 3 PS C:\Users\antonius> write "Hello World!" Hello World! PS C:\Users\antonius> echo "Hello World!" Hello World!

Sure enough, we found both yield the same result

We might wonder, "Why are there two aliases for the same command?" I don't really know the answer to that question other than perhaps the alias write is the built-in alias for Write-Output and perhaps the alias echo is simply a way to help those who are used to writing .BAT scripts to transition a little more easily to Windows PowerShell. Whatever the answer to that question is rather irrelevant; what's more important is that now we've gone through the basic exercises in learning each PowerShell command.

Wait wait wait!!! We're not done here!

What's all that business with the where command and the rest of the strings following it?

No, I didn't cheat :)

I simply wanted to shortcut all the trial and errors I went through in learning PowerShell without filling the content of this notes full of garbage. Trial and errors, after all, are things we each can do individually on our own time. As for the shortcut strung with the where command, I'll note an explanation of it another time.

Basic Windows PowerShell Commands

Windows PowerShell is relatively new shell command interpreter in comparison to the venerable CMD, CScript, and Windows Script Host.

Just like any shell script, it isn't really difficult to learn simply by trial and errors as long as we get the few basic commands down so we can drill further to other commands we seek to use.

The most basic command we should know is, of course, help.

Get-Help

As the command name suggests, it is the single command we use to see the details of a particular command we submit as a parameter to the help command. Listing 1 below illustrates the help command execution.

Listing 1: PS C:\Users\antonius> help help NAME Get-Help SYNOPSIS Displays information about Windows PowerShell cmdlets and concepts. SYNTAX Get-Help [[-name] <string>] [-component <string []>] [-functionality <string []>] [-role <string []>] [-category <string []>] [-full] [<commonparameters>] Get-Help [[-name] <string>] [-component <string []>] [-functionality <string []] [-role ><string []>] [-category <string []>] [-detailed] [<commonparameters>] Get-Help [[-name] <string>] [-component <string []>] [-functionality <string []>] [-role <string []>] [-category <string []>] [-examples] [<commonparameters>] Get-Help [[-name] <string>] [-component <string []>] [-functionality <string []>] [-role <string []>] [-category <string []>] [-parameter <string>] [<commonparameters>] DETAILED DESCRIPTION The Get-Help cmdlet displays information about Windows PowerShell cmdlets and concepts. You can also use "Help {<cmdlet nam e> | <topic-name>" or "<cmdlet-name> /?". "Help" displays the help topics one page at a time. The "/?" displays help for cm dlets on a single page. RELATED LINKS Get-Command Get-PSDrive Get-Member REMARKS For more information, type: "get-help Get-Help -detailed". For technical information, type: "get-help Get-Help -full".

It's so helpful that we can simply type help help at the prompt to display the details of the help command itself. As we examine the command output's "Related links" section, we see three other commands related to the help command. All the three new commands we found here: Get-Command, Get-PSDrive, and Get-Member are part of the important basic commands we will discuss more thoroughly a little later.

Get-Aliases

"Shallow Hal wants a gal."

The second basic command that is most useful to expedite our PowerShell command study is Get-Aliases also aliased as gal. First, we're gonna combine gal with the first command we learned earlier: help in Listing 2. Then, we'll try to see if sending the command twice to the shell prompt, one as the command call itself and another as the paramater to the command call gal gal in Listing 3.

Listing 2: PS C:\Users\antonius> help gal NAME Get-Alias SYNOPSIS Gets the aliases for the current session. SYNTAX Get-Alias [[-name] <string []>] [-scope <string>] [-exclude <string []>] [<commonparameters>] DETAILED DESCRIPTION The Get-Alias cmdlet gets the alternate names for cmdlets, functions, and executable files that have been established for the current session. This collection includes built-in aliases, aliases that you have set or imported, and aliases that you have added to your Windows PowerShell profile. If you specify one or more aliases, Get-Alias gets the alias object and displays its properties, including the object that was aliases, such as the full name of a cmdlet. This feature is made available by the Windows PowerShell Alias provider. RELATED LINKS Set-Alias New-Alias Export-Alias Import-Alias REMARKS For more information, type: "get-help Get-Alias -detailed". For technical information, type: "get-help Get-Alias -full".Listing 3: PS C:\Users\antonius> gal gal CommandType Name Definition ----------- ---- ---------- Alias gal Get-Alias

See! It's simple right? From Listing 2, we find the usage details of the command gal, and from Listing 3, we find that gal itself is an alias of the command Get-Aliases.

But, but, but... How did I know in the beginning that help and gal are commands we can execute? The answer is as ordinary as it could be—I guessed the first command: help presuming that a program usually has a variation of help, --help, --h, man or the old-school /? in some sort of form even without reading its documentation. As for the command: gal, after having found out that while the command help could be executed and yields an output indicating the actual command name: Get-Help, I simply sought in MSDN PowerShell site a reference entry pertaining to available command aliases.

Up next... We won't need to go through the details of each command, but will start our PowerShell exercises by using the three new "related" commands we learned earlier from Listing 1.

One ID to rule them all!

Having an OpenID is a cool thing. In theory, I wouldn't have needed to register for any other account ever. Alas, most ideals are just that: ideals. No, I'm not saying anything bad against OpenID; I'm only saying that even with the best intention we still frequently are unable to realize the full potential of the idea's ideals.

Take SourceForge.Net for example, it's one of sites I frequented. Sure it does take my OpenID to authenticate me when I logged into the site, but it still requires me to bind to a local SourceForge account if I want to use it to access certain things such as its CVS repositories. C'est la vie.

The OpenID provider I chose for my use is MyOpenID.com. I like MyOpenID.com because it is one of only a few (as of this writing) strong authentication providers who uses SSL certificates and Windows CardSpace/InfoCards which enables auto-authentication. This is so that while I do have a password for my OpenID account, I won't need to really memorize it or use it to sign into any sites using my OpenID account.

To demonstrate:

1. Go to MyOpenID.com
2. Sign in (if you already have an OpenID account)
   
3. Choose a sign-in method
   
   Or
   
4. You'll be presented with a certificate you've previously created and install in your browser
   
   Or be prompted to send your Microsoft Windows InfoCard you've previously linked to your OpenID
   
5. Click sign-in
   
6. And swweeet!! I'm in... quick & easy.

How to write clean website layout using CSS (Part 2)

The pure <div/> approach: Positions

Creating web page layout using CSS positioning really is a very simple thing to do. All we need to remember is that an XHTML element's absolute position is always relative to its container. That is the one thing we usually forget. We are so caught up in the semantic definition of the word absolute position we forget that it isn't absolute only in the context of the web page itself (<body/>).

For a similar simple markup we wrote in Listing 2 of our previous notes, we now have the following Listing 1.

Listing 1: <body id="doc"> <div id="d11" class="d1"> <div id="d11-sub1"> <div id="d11-21" class="d11-2"> </div> <div id="d11-22" class="d11-2"> </div> </div> <div id="d11-sub2"> <div id="d11-23" class="d11-2"> </div> <div id="d11-24" class="d11-2"> </div> </div> </div> <div id="d12" class="d1"> <div id="d12-21" class="d12-2"> </div> <div id="d12-22" class="d12-2"> </div> <div id="d12-23" class="d12-2"> </div> <div id="d12-24" class="d12-2"> </div> <br style="clear: both" /> </div> <br style="clear: both" /> </body>

The styling commands we needed in Listing 2 felt simpler to do and easier to understand from the perspective of having to think about how the browser layout engine will interpret the commands we write.

Listing 2: /* Section: Content specific **********************************************************************/ body, #doc { border: 5px double rgb(255,0,0); width: auto; /* Use // to give a specific instruction to IE browser only **********************************************************************/ //padding-bottom: 100px; } #d11, #d12 { height: 100%; width: 920px; border: 5px solid rgb(0,255,0); margin: 100px; /* Set margin-{left, right} to &quot;auto&quot; to center the div box because * setting text-align to &quot;center&quot; at the container level only works * with IE but not with other browsers, in addition to having the * unintended effect of having the container's text actually centered * that is if we simply just want the layouts centered, not its text. **********************************************************************/ margin-left: auto; margin-right: auto; } div.d11-2 { border: 5px solid rgb(0,0,255); margin: 50px; } #d11-sub1, #d11-sub2 { width: 900px; height: 100%; border: 1px solid red; margin: 10px; position: relative; } #d11-21, #d11-22, #d11-23, #d11-24 { width: 100px; padding: 25px; } #d11-22 { position: absolute; top: 0px; right: 0px; } #d11-24 { position: absolute; top: 0px; right: 0px; } #d12 { border: 5px solid rgb(0,150,50); } div.d12-2 { border: 5px solid rgb(0,0,255); margin: 50px; } #d12-21, #d12-22, #d12-23, #d12-24 { padding: 10px; width: 100px; float: left; } /* End Section **********************************************************************/

I'd say it looks pretty straightforward without having spent lots of hours tweaking the style attributes to get the desired results.

I was pretty happy this turned out to be easy. But then just for kicks I wanted to find out "What if I did the other way around, strictly with floats and kept all the elements' positions at its default relative value?" "Would it be just as simple?" "Would it be just as quick to do?"

The pure <div/> approach: Floats

With the same base structural template as Listing 1 above, I found that achievement the desired result using float method is considerably longer. Sure if you look at the last CSS code-block of Listing 2, you'll see that I actually cheated by using floats because well... that was actually the simplest way to order the <div/>'s in simple column formation. But then, to figure out which of the <div/>'s in square formation need to be floated the right way took quite a bit of trial and error in the order of magnitude of 5. Yes. Five. Listing 2 took me only a couple of minutes to write and get right. Listing 3 took me almost 15 minutes to do due to tinkering with the float and clear attribute combinations.

Listing 3: /* Section: Content specific **********************************************************************/ body, #doc { border: 5px double rgb(255,0,0); //padding-bottom: 0; } #d11, #d12 { width: 920px; border: 5px solid rgb(0,255,0); margin: 100px; /* Set margin-{left, right} to &quot;auto&quot; to center the div box because * setting text-align to &quot;center&quot; at the container level only works * with IE but not with other browsers, in addition to having the * unintended effect of having the container's text actually centered * that is if we simply just want the layouts centered, not its text. **********************************************************************/ margin-left: auto; margin-right: auto; } div.d11-2, div.d12-2 { border: 5px solid rgb(0,0,255); margin: 50px; } #d11-21, #d11-22, #d11-23, #d11-24 { width: 100px; padding: 25px; } #d11-sub1, #d11-sub2 { border: 1px solid red; margin: 10px; //padding-bottom: 50px; } #d11-21, #d11-23 { float: left; clear: left; } #d11-22, #d11-24 { float: right; clear: right; } #d11-23 {clear: left;} #d12 { border: 5px solid rgb(0,150,50); } #d12-21, #d12-22, #d12-23, #d12-24 { padding: 10px; width: 100px; float: left; } #d12-21 {clear: left;} #d12-24 {clear: right;} /* End Section **********************************************************************/

How to write clean website layout using CSS (Part 1)

There are three well-known techniques in creating a website layout using CSS:

1. The <table/> approach.
2. The <table/> + <div/> hybrid approach.
3. The pure <div/> approach.
   1. The positioning approach of absolutists v. relativists; and,
   2. The clearing float (or is it the floating clear? <smile/>).

There are others of course; very advanced CSS masters like to further enhance the cleanliness of their XHTML code without using a single <div/> or <span/>.

As I jumped into refresher exercises, I wondered: "How easily would it be for me to do this (ref: screen)?" Or, "Is it even possible to easily do it for the four popular browsers today?"

---

Warning: At the time of writing, the following materials were only proofed on:

• Internet Explorer 7.0.6001.18000
• Firefox 3.0.6
• Safari 3.2.2 (525.28.1)
• Chrome 1.0.154.48

This article merely documents these variations and choices. We do not advocate one approach versus another as these choices are left to each of our individual circumstances and reasons. Although <grin/> I would soon give up doing the first approach.

The base skeletal structure for each of the tested approaches is the following Listing 1(with slight differences):

Listing 1: <!--xml version="1.0" encoding="UTF-8"?--> <!--DOCTYPE html PUBLIC "-//W3C/DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml1-transitional.dtd"--> <html> <head> <title>DIV</title> <style type="text/css" media="all"> /* Section: Initialization **********************************************************************/ * { margin: 0px auto; padding: 0px; outline: 0 border: 0 none; font-family: cambria, georgia, "Times New Roman", times, serif; font-size: 11pt; font-style: inherit; font-weight: inherit; vertical-align: baseline; text-decoration: none; /* Set min-height to "100%" and overflow to "auto" in order to set * the div box to stretch to the height of its children elements. This * setting bears no effect whatsoever on IE. **********************************************************************/ min-height: 100%; /* Use // to give a specific instruction to IE browser only **********************************************************************/ } } body { padding: 10px; } h1, h2, h3, h4, h5, h6, p, pre, blockquote, form, ul, ol, dl { margin: 20px 0; } ul, ol, dl {list-style: none;} table, tr, td { border-spacing: 0; } a img, :link img, :visited img, { border: 0 none; vertical-align: bottom; } code, .code{ padding: 10px; padding-left: 15px; font-family: consolas, monaco, "Courier New", courier, monospace; font-size: 9pt; color: rgb(100,100,100); white-space: pre; text-align: left; } /* End Section </style> </head> <body> ... </body> </html>

---

The <table/> approach

If we search the Internet for arguments against using <table/> tags for layout purposes, we will find them in abundance. They are all valid arguments and we should heed them. I simply could not bring myself to nest <table/> tags like it's 1999.

The <table/> + <div/> approach

For the following simple layout in Listing 2:

Listing 2: <body> <table> <tr> <td id="t11-21"> <div id="d11-21" class="d11-2"> </div> </td> <td id="t11-22"> <div id="d11-22" class="d11-2"> </div> </td> </tr> <tr> <td id="t11-23"> <div id="d11-23" class="d11-2"> </div> </td> <td id="t11-24"> <div id="d11-24" class="d11-2"> </div> </td> </tr> </table> <table> <tr> <td id="t12-21"> <div id="d12-21" class="d12-2"> </div> </td> <td id="t12-22"> <div id="d12-22" class="d12-2"> </div> </td> <td id="t12-23"> <div id="d12-23" class="d12-2"> </div> </td> <td id="t12-24"> <div id="d12-24" class="d12-2"> </div> </td> </tr> </table> </body>

We still had the following styling code in Listing 3

Listing 3: /* Section: Content specific **********************************************************************/ body, #doc { width: 100%; border: 5px double rgb(255,0,0); //padding-bottom: 100px; } table { width: 948px; border: 5px solid rgb(0,255,0); margin: 100px; /* Set margin-{left, right} to &quot;auto&quot; to center the div box because * setting text-align to &quot;center&quot; at the container level only works * with IE but not with other browsers, in addition to having the * unintended effect of having the container's text actually centered * that is if we simply just want the layouts centered, not its text. **********************************************************************/ margin-left: auto; margin-right: auto; table-layout: fixed; } /* TR styling doesn't work on IE ************************************************************************/ tr { width: 928px; border: 5px solid red; display: block; } td { vertical-align: top; } #t11-21, #t11-23 {width: 100%;} #t11-22, #t11-24 {text-align: right;} #t11-21, #t11-22, #t11-23, #t11-24 { //width: 50%; border: 1px solid blue; } #t12-21, #t12-22, #t12-23, #t12-24 { width: 25%; text-align: center; border: 1px solid blue; } div.d11-2, div.d12-2 { border: 5px solid rgb(0,0,255); margin: 50px; } #d11-21, #d11-22, #d11-23, #d11-24 , #d12-21, #d12-22, #d12-23, #d12-24 { text-align: left; width: 100px; padding: 25px; overflow: visible; } #d12-21, #d12-22, #d12-23, #d12-24 { padding: 10px; //margin-left: 0px; //margin-right: 0px; } /* End Section ************************************************************************/

Yes, this approach yields a slightly cleaner code result than only the <table/> based approach. But it isn't without its own problems. There's that <tr/> rendering issue in IE. And of course, I found that the CSS implementation differences between the various browsers render this approach virtually indefensible, as in saying: "If we have to resort to using various CSS tricks/hacks anyway, why not simply do a Table-less Layout with its pros and cons already weighed by the web design community at large, especially when we already have ample samples written by masters such as those from A LIST apart and Zen Garden—two sources of my favorites reading materials where I found a wealth of knowledge shared to us all common netizens."

Need I say more?

Up next: The pure <div/> approach (Part 2).

How to create a new Blogger template (Part 2)

Blogger's Layout Data Tags

As of this writing, a Blogger's template document requires at least a skin declaration, usually placed in the document header as seen in Listing 1 below.Listing 1: <b:skin><!--[CDATA[ /* Blogger only allows exactly one (1) <b:skin/--> element be defined * in the template document. * Although this is essentially where we place our global CSS code, * we can still declare style blocks or inline style attributes as * usual just like the example below. */ .globalStyleClass { definitions; } ]]></b:skin> <style type="text/css"> .standardstyleclass { definitions; } </style>

For details on why tag is required read this Blogger Help article—that is, if you want to integrate your customized template to Blogger's WYSIWYG layout editor.

That's pretty much it. The rest, we can just drop widget definitions following this Blogger Widget article and regular X/HTML web-design exercises.

The following is the result of this new Blogger template exercise.

Before:

To what we're seeing now.

How to create a new Blogger template (Part 1)

1. Start with a Blogger's basic default template and dissect it.
2. Understand basic X/HTML coding.
3. Understand Blogger's Layouts Data Tags
4. Know where to find help for customizing Blogger's template.

Dissecting a Blogger's basic default template

Leave the first two lines alone.

Listing 1:
<?xml version="1.0" ...?>
<!DOCTYPE html PUBLIC "... XHTML 1.0 Strict//EN"... >

After the first two lines of code, a Blogger's template is essentially just a regular X/HTML document (according to the specified DOCTYPE in code line #2).

Side notes: Personally, I use XHTML 1.0 Transition for reasons we'll experience when we exercise the coding style I wrote in here: How to write clean X/HTML document. For this reason, in the remaining content of this study assumes and follows the transitional document type declaration.

Basic X/HTML coding

An X/HTML document essentially consists of simple structural tags as seen in Listing 2 below.

Listing 2: <html> <head> <style></style> <script></script> </head> <body> </body> </html>

Despite all of the content we see when view an X/HTML document on the web, that's really all there is to it. A Blogger's template is no exception. The some differences we see in the basic template we've downloaded usually has to do with what Blogger labels "Layout Data Tags" or, for those used to using Blogger's WYSIWYG layout editing tool, "Widgets" (regardless of whether or not they're displayed on the resulting browser screen).

In Blogger's document template case, there are extra namespaces declared as attributes of the <html> tag as shown in Listing 3 below.

Listing 3: <html xmlns="http://www.w3.org/1999/xhtml" xmlns:b="http://www.google.com/2005/gml/b" xmlns:data="http://www.google.com/2005/gml/data" xmlns:expr="http://www.google.com/2005/gml/expr" expr:dir="data:blog.languageDirection"> ... </html>

We should do the same.

How to write clean X/HTML document

---

Warning: XMP tag is an officially deprecated tag as of HTML specification 3.02. So follow this advise at your own risk.

---

Use <xmp/> tag instead of the using many <br/> tags to pre-format ourmultiline texts inside a <p> tag. We should use <xmp/> tag for plain text and demonstrated code listings instead of using escaped stuff (entities) such as &lt; and &gt; Escaping characters are such tedious chores and we are all better off with using <xmp/> tag. If we want to have the HTML content of our tags still interpreted as HTML content then we choose to use the <pre/> tag instead of <xmp/> tag (ref: Listing 1) Listing 1: <pre> <b><u>HI THERE!</u></b> XMP is sweet. I don't know why such as useful tag is deprecated. </pre> Listing 1 will still be interpreted as HTML content and render as the following: (notice how the rendered text includes the invisible 'tab' characters). Let's compare it to what we would have to do in Listing 2 below if we don't use <xmp/> Listing 2: &nbsp;&nbsp;&nbsp;&nbsp;<b><u>HI THERE!</u></b><br/> &nbsp;&nbsp;&nbsp;&nbsp;XMP is sweet.<br/> &nbsp;&nbsp;&nbsp;&nbsp;I don't know why such as useful tag is deprecated.<br/> Which codeblock is easier to work with? Just for writing:

	HI THERE!
	XMP is sweet.
	I don't know why such as useful tag is deprecated.

We could alternatively use CSS to control our content like the following: Listing 3: <p style="white-space: pre;"> My multi line content inside a paragraph &lt;p/&gt; tag </p> to render the following:

My multi line content inside a paragraph <p/> tag

Although the sample in Listing 3 takes the white-space character and carriage-return/line-feed character, it does not take the tab character and other invisible characters that may be inside our text content-not to mention more typing compared to using <pre/> tag. If it is still chosen, IE will fault us (if we are reading this using IE, we will see the above example above as a single-line, instead of what it should be). Using the <xmp/> tag and/or <pre/> tag helps us reduce the mess that other developers would see when they view the source of our program. What mess am I talking about? Think about this: How often do we use &nbsp; like the above example? Yep, that's what I'm talking about :) So what if we want to stylize an <xmp/> content?

All we have to do is use a CSS class as we would in any other case:
For example: we could do the following:
Listing 4:
<xmp style="color: blue; font-weight: bold;">Content</xmp>

Such that the result renders as the following: Content We should be careful and test the use of <xmp/> tag carefully since this tag has been officially deprecated as of HTML standard 3.02 and is replaced by the <pre/> tag (see: WARNING at the top of this page), despite the fact that the <pre/> tag is available, it doesn't completely offer all the simple escaping facilities offered by the <xmp/> tag.