doc/faq.html

<h1><a name="generic">Generic Questions</a></h1>

<h2><a name="whatis">What is webshell ?</a></h2>

webshell is a rapid development environment for building powerful and
reliable web applications. It is a standard Tcl extension and is
released as Open Source Software. webshell is versatile and handles
everything from HTML generation to data-base driven one-to-one page
customization. At Netcetera, we have been using it for years for
virtually all our customer projects, which typically are E-commerce
shops or electronic banking applications.

<h2><a name="version">What is the current version ?</a></h2>

Currently, we are finalizing version 3 of webshell. webshell 3 will be
available for download starting Mar 1, 2000.

<h2><a name="price">What does webshell cost ?</a></h2>

Nothing. It's free. webshell is released as Open Source.

<h2><a name="download">Where can I download webshell ?</a></h2>

webshell will be available for download starting 
Mar 1, 2000 at the &lt;a href=&quot;download.html&quot;&gt;download area&lt;/a&gt; of this site.

<h2><a name="netcetera">Who is Netcetera ?</a></h2>

Netcetera is a software company which mainly focuses on Internet
services, particularly in the area of electronic commerce. Netcetera
is located in Zurich, Switzerland. We offer a wide range of services,
including consulting and conceptual design, project management, and
software development for Internet technologies. It is our goal to
deliver high-quality products at the forefront of technological
development. Netcetera is focused on developing and maintaining its
core technical competence. In order to offer high quality in all
aspects of our products, we cooperate with the main players in the
field. For example, the look-and-feel of our applications and web
pages is designed by communication experts.  Netcetera cares for its
customers.

Find more information about Netcetera at our 
&lt;a href=&quot;http://netcetera.ch&quot;&gt;homepage&lt;/a&gt;.

<h2><a name="why">Why should I use webshell ?</a></h2>

In today's E-commerce environment, flexibility and short
time-to-market are key characteristics for successful
business. E-commerce, in other words, calls for a solid basis on which
applications can be built. For exactly this purpose we have designed
webshell.

<br><br>
webshell helps you to create high-quality web applications with light
time constraints. It is fast, versatile, scalable, and easy to learn.
With webshell, you have a win-win situation for developers and
customers.

<h2><a name="mailinglist">Is there a mailing list ?</a></h2>

Yes, Netcetera edits a quarterly newsletter for webshell.  You can
subscribe to the newsletter from www.websh.com/subscribe.html, or by
sending an e-mail to majordomo@netcetera.ch with &quot;subscribe
websh-news&quot; in the body of the message.

If at any time you would like to unsubscribe from this newsletter, you
may do so at www.websh.com/unsubscribe.html, or by sending an e-mail
to majordomo@netcetera.ch with &quot;unsubscribe websh-news&quot; in the body of
the message.

<h1><a name="technical">Technical Questions</a></h1>

<h2><a name="convert">I am  websh2 wizard. How do I switch to websh3 ?</a></h2>

Converting to websh3 is straight forward:

<ul>
<li>change all command nmes from wpp_ to web::
<li>change a few comans where the syntax differs from websh2 (see quickref):
 - wpp_isselected
 - wpp_ischecked (both with web::match)
 - wpp_loglevel is web::logfilter
 - wpp_logrule is web::logdest
 Note that web::log evaluates the messge. Thus, you should write it in {}
 - check syntax of web::config
<li>add web::dispatch at the end of you script
</ul>

Netcetera AG has written a compatibilty layer for websh2. This allows
you to run entire websh2 applications with websh3 without changing a
single line of your code.

<br><br>
<h2><a name="logging">How do I use the logging facility ?</a></h2>

Before webshell sends a message to a log destination, the message
needs to pass two filters. That's why you need to specify a level when
you issue a log message. First, webshell decides whether or not to
handle the log message. Then, it scrolls through the list of
registered log destinations and compares the log message level against
the filter of each log destination. The message is sent to the log
destination only if the message passes the second filter.

<br><br>
A log level consists of a tag and a level, separated by a dot.
Possible levels are
<ul>
<li>alert
<li>error
<li>warning
<li>info
<li>debug
</ul>
The tag is free text. Typically, it is the name of the application, 
say &quot;foo&quot;.

<br><br>
Before log messages can reach their destination, you have to
&quot;open up&quot; the log destination, in two steps:
<pre>

web::logfilter add foo.warning-debug
web::logdest add foo.warning-info file foo_warn.log
web::logdest add foo.debug file foo_dbg.log

</pre>

This sequence of commands tells webshell to handle all messages
in the range &quot;warning&quot; to &quot;debug&quot;, if the level string is
&quot;foo&quot;, and to discard any other messages. Messages of level
&quot;debug&quot; are then written to file &quot;foo_dbg.log&quot;, while
the other messages end up in file &quot;foo_warn.log&quot;.

<br><br>
Issuing a message is easy:
<pre>

web::log foo.info &quot;Hello, world !&quot;

</pre>