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Homework and Emergencies Homework & Coursework Questions Negation
# 1  
Old 03-23-2011
Negation
Hello, have anybody any idea, how to negate some expression?

I have code that greps somethnig and I want filter from it some results...How to make it?

IDontWantThisExpression=$1
grep 'some regex' | grep '$IDontWantThisExpression' testfile.txt

Thanks for any advices.

Faculty of Mathematics and Physics, Charles University in Prague, The Czech Republic, Ondrej Tichy, ms.mff.cuni.cz/~ticho6am
# 2  
Old 03-24-2011
Code:
grep -v <IDontWantThisExpression> filename

# 3  
Old 03-24-2011
yes! -v switch Smilie thanks Smilie
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