Other Tools

The Tcl community has built many interesting and useful tools to help your Tcl development. Only two of them are mentioned below, but you can find many more at the Tcl Resource Center:

http://www.tcl.tk/resource/

The tkcon Console

Tkcon is an enhanced Tk console application written purely in Tcl. It includes many useful interactive control features, and may be embedded in other Tcl applications. It was written by Jeff Hobbs and you can find it at:

http://tkcon.sourceforge.net/

Critcl

Critcl is a tool that lets you mix C code right into your Tcl scripts. When the cproc command encounters its code for the first time, it automatically compiles it with gcc and loads it into your application. This provides an easy way to recode small parts of your application in C to get a performance boost. It's home page is:

http://www.equi4.com/critcl

The bgerror Command

When a Tcl script encounters an error during background processing, such as handling file events or during the command associated with a button, it signals the error by calling the bgerror procedure. A default implementation displays a dialog and gives you an opportunity to view the Tcl call stack at the point of the error. You can supply your own version of bgerror. For example, when my exmh mail application gets an error it offers to send mail to me with a few words of explanation from the user and a copy of the stack trace. I get interesting bug reports from all over the world!

The bgerror command is called with one argument that is the error message. The global variable errorInfo contains the stack trace information. There is an example tkerror implementation in the on-line sources associated with this book.

The tkerror Command

The bgerror command used to be called tkerror. When event processing shifted from Tk into Tcl with Tcl 7.5 and Tk 4.1, the name tkerror was changed to bgerror. Backwards compatibility is provided so that if tkerror is defined, then tkerror is called instead of bgerror. I have run into problems with the compatibility setup and have found it more reliable to update my applications to use bgerror instead of tkerror. If you have an application that runs under either Tk 4.0 or Tk 4.1, you can simply define both:

proc bgerror [info args tkerror] [info body tkerror]