02.03.2014 Views

Tornado

Tornado

Tornado

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

B<br />

Tcl<br />

B.1 Why Tcl?<br />

Much of the <strong>Tornado</strong> implementation is written in Tcl (the tool command language<br />

designed by John Ousterhout). Readers who are already familiar with Tcl<br />

applications are not likely to find this surprising.<br />

However, if Tcl is new to you, you may be wondering why. Choosing Tcl as the<br />

implementation vehicle has the following benefits:<br />

■<br />

Customization: <strong>Tornado</strong> can be customized to an unprecedented degree. All<br />

tools can be conditioned with Tcl scripts. At a deeper level, the Tcl code for the<br />

tool itself is available for your inspection. This allows you to more easily write<br />

your own Tcl code to modify any features you wish to change.<br />

! CAUTION: When you customize <strong>Tornado</strong> tools, write your changes as<br />

separate files that override the original tools. That way, <strong>Tornado</strong> WRS technical<br />

support can still help you, if the need arises; and it will be easier to preserve<br />

your enhancements over new releases of <strong>Tornado</strong>.<br />

■<br />

Development speed and robustness: Because development in Tcl is<br />

interactive, graphical-tool design can include much more experimentation in<br />

the development cycle. This means we at WRS can build products faster, and<br />

we can build them better, checking our results as we go. Third-party<br />

developers experience exactly the same benefits. All of this means that you, the<br />

VxWorks application developer, have more and better tools available to choose<br />

from.<br />

■<br />

Ease of maintenance: Because Tcl code is ordinary text, optional products and<br />

third-party add-ons can integrate themselves into a <strong>Tornado</strong> installation by<br />

317

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!