The first script in Clipboard transform keys takes the Win32 clipboard, execs it, and stuffs the results back. I know that this is a no-no in terms of security, but it is a script that only I use on my local machine, will never be exposed to the internet, and only processes the clipboard contents anyway. This is the latest version of the clipboard calculator.

My question is: If I did want to improve the security while retaining the functionality, how would I go about it? Does exec go out the window entirely?

How, for instance, would you go about implement something like Google Calculator?

Update:The purpose of the code is to do mathematical calculations. I got fed up of switching to Calc and doing it there, and losing the results of old calculations, so now I do all my maths in a text editor. Given this input:

4*3
11-4*2
it produces this output:
4*3 =	12
11-4*2 =	3

In reply to Hardening an exec-based script by PhilHibbs

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