Can I do this without eval? (zsh)


 
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Old 01-25-2017
Quote:
Originally Posted by Corona688
I definitely reccommend against injection rejection which leaves you wide open to things you don't know about and can react badly to valid things you still didn't expect. (What if a filename contains a literal backtick?) Better to not leave the door open in the first place and use something which doesn't allow for shell interpretation.
Backquotes are harmless. In this case, the code to be eavl'ed would at worst be something like

Code:
[[ ! -d '`rm -r *`' ]]

and this wouldn't actually execute the rm, due to the surrounding single quotes. But of course, whenever I do injection rejection, it might be that I overlook some corner case. So while I believe that my solution is safe, there is always some bad feeling that I might have missed something.

I verified, that test indeed is a builtin in zsh too, so it really makes sense using it here.
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