Need help with function

Hello,

Perhaps you could help me with this function: I need a function that puts 
a string with the actual filename, a colon and the line of point into the 
X Clipboard. It should look like this:

CPTClassname.cpp:42

I want to paste this to DDD ...

I came up with this so far, but emacs complains:
"Invalid function: (own-clipboard (file-name-nondirectory 
buffer-file-name))"

(defun mg-copy-position()
  "Copy a string of the form filename:linenumber into the clipboard"
  (interactive)
  ( (own-clipboard (file-name-nondirectory buffer-file-name) ) )
  )

As you see, It also completely lacks the combination of filename, ":" and 
line...

Any help will be welcome,

Markus Grunwald
Softwareentwicklung

PRÜFTECHNIK Condition Monitoring GmbH
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www.pruftechnik.com
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