In-place file record modification

From: Andy (kaleanand_at_gmail.com)
Date: 12/27/04 

Date: 27 Dec 2004 01:40:51 -0800

Hi,

I would like to know if one can do in-place file editing in Tcl.
Example:
I have record such as
0078 100,99,10,11,11,0,0

to be replaced by
0078 100,99,10,11,11,7,9

Can one replace this record in this file without creating a new
file ?

Thanks in advance,
Anand