10 April 2003
Question & Answer Sessions
- Where are we meeting next month?
- Washtenau Community College is one posibility. A private school
down the street might host us for a month or two. Second Floor of
Zingerman's. Sidetrack Saloon in Depottown has room we might be
able to get on Thursdays. We had a few meetings at Cooker back
in the days before ITI. There's also the Wrap House in Kerrytown.
Currently, the answer is "I don't know."
- Why are we asking that question?
- Larry Plato is moving on and we no long have a sponsor at Cisco.
- eTools by Wizards of the Coast print problems -- ideas?
- No ideas. Probably need to talk to WotC about it. (They're good
- What does the -eq flag in sendmail do?
- "Don't print any error messages," according to sendmail 8.6.9.
- What's up with Sendmail this time?
- Someone found a bug, but no exploit. Things got confusing after that.
(An exploit was claimed, but it wasn't viable.)
- What's an HP8000 good for?
- About thirty-two feet per second squared. It's big and clunky
and a couple generations old. It's faster than most recent
- Favorite imapd?
- MJO prefers Cyrus to UWash one.
- FreeBSD 4.8 - anyone running it?
- The second floppy is a little too big; use the 4.7 disks and
play with the options until they fix the 4.8 ones.
- snort rocks?
- No thanks, it hurts too much. (Ouch.)
Clif is playing with a firewall validator and is curious about
whether snort signatures can be used to help with the task.
- Does anyone want to be an a panel at Pengicon?
- Write to John Guest if you're interested.
- Any free virtual machines besides bochs?
- Not really.
- Why not bang?
- Because Larry has an attitude.
- Pushing Celeron processors?
- No good ideas.
- HP has made noises about jobs at Ford. There have been a bunch
of operations postings at Ford.
- Want to buy Troy's ST-1100?
- If so, contact Troy.
- Does Troy need a housemate?
- Connectix virtual PC -- what's Microsoft up to?
- Who knows ... it's Microsoft. Rumor has it they're trying to get
their GUI running on top of FreeBSD.
- Why didn't the dourbell work the first three times?
- Why are you so impatient?
- What's nsb been upto?
- Commuting to New England (IBM Lotus Div.). Expect to hear more later.
- Is anyone using argus?
- Any recommendations for places to eat in Vancouver?
"Tcl/Tk Wrappers for Non-GUI Programs" with Clif Flynt
Extending Application with Tcl/Tk
- Type of applications designs
- Strengths of split functionaltiy designs
- GUI designs
- GUI with Tk and BWidgets
- Controlling a slave applciation with Tcl
- Displaing results with Tk and BWidgets
Computer applications can be divided into two types:
Application includes user
interface and analysis code.
The single application pro...
If an application is present,
Tight linkage between UI and
Analysis can create maintenance
Any new functionality requires
Why use a scripting language for User Interface?
- A user interface may require frequent modifications
- During development, the analysis module may change functionality.
- After deployment, User Interface paradigms change and an
application must be upgraded to confirm to user expectatiosn
- Changing the underlying interpreter can upgrade all applications
simultaneously and painlessly.
- User Requirements _will_ change
- User Interface works with strings, not internal representations
Tcl is ...
... An Embeddable Interpreter
... An Extensible Interpreter
... An application Glue Language
... GUI oriented graphics package
... Commercially supported
Tcl is Commercially Supported Freeware
Tcl/Tk interpreters were developed at UC Berkeley with US tax dollars.
This, the core interpreters must remain free.
Why use Tcl/Tk?
- Tcl supports multiple styles of controlling analytic module:
- Controlling a subtask
- exec: Execute a task and capture the output
- open pipe: Read task output as it becomes available
- expect: Interact with task
- socket: Interact with remote task
- Interfacing with a library
- Create an extension and write application as Tcl script
- Embed Tcl in application and use Tcl to read configuration files.
- Tcl/Tk graphics library
- Many existing Tcl extensions and pure Tcl packages
- Tcl is multi-platform
1. Tested on FreeBSD and several flavors of Linux
2. Reads /proc/cpuinfo or exec's dmesg to get basic CPU facts
3. Uses exec to collect network statistics via netstat
4. Uses open| to collect activity from top.
5. System interaction code is separate from display code.
Uses trace to invoke GUI.
6. Uses BWidgets for main panels
7. Use barchart and piechart to display information graphicly.
[ Clif says the slides will be available later ... ]
[ This all looks pretty handy, kids. ]
You can find Clif at:
10th Annual Tcl/Tk Conference July 29-Aug 2 <http://www.tcl.tk/>
WCC Tcl/Tk Course <http://www.washtenaw.cc.mi.us/>
Noumena Corporation (firstname.lastname@example.org) <http://www.noucorp.com/>
Rumor & Innuendo (No names, please)