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Removing control characters using tcl

Posted by awalia (awalia), 28 January 2007
Hi I want to write tcl script to remove the following control characters from a file.


For this I want to use "sed". I have been succesful in doing the third and the fourth using eval and sed, but have no success with the first two.

Note: I do know that to have control character ^M, I have to use Ctrl+V and Ctrl+M.

Posted by admin (Graham Ellis), 29 January 2007
I would use regsub.   There's an example that converts all control characters into their unicode equivalents here which should get you started.  Please post up sample code if you have any further problems, or indeed if you get it working, please let us know with an example that others can learn from too.   Thanks!

Posted by awalia (awalia), 29 January 2007
This is how I remove the characters ^H and ^[

eval "exec sed \"s/^H//g\" | sed \"s/^[//g\" < file1 > file2"

Posted by admin (Graham Ellis), 30 January 2007
I would use regsub.  Tcl is perfectly capable of making the changes you need without using another language / program.  

I've just noticed that you said "I want to use sed", though.   Why?  It seems an odd way to go ...

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