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grep -v and regex


 
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# 1  
Old 10-20-2011
grep -v and regex

How to match lines that don't contain a patern in regex it self, without using the -v option of grep?
# 2  
Old 10-20-2011
More details, please! If you post sample input and example of the expected output.
... and, why "without using -v"?
# 3  
Old 10-20-2011
You are saying to negate insite the regex? Like:
Code:
'[^abc]'

It means, not abc.
# 4  
Old 10-20-2011
The obvious solution to matching lines that don't match a regular expression without resorting to grep -v would be to not use grep at all.
Code:
sed -n '/regexp/!p'

I realize that my response could be construed as sarcasm, but it's not.

Why is grep's -v unavailable? Does the implementation not provide it? If not, which platform are you on? I'm always curious about these situations.

Regards,
Alister
# 5  
Old 10-20-2011
Quote:
Originally Posted by alister
The obvious solution to matching lines that don't match a regular expression without resorting to grep -v would be to not use grep at all.
Code:
sed -n '/regexp/!p'

I realize that my response could be construed as sarcasm, but it's not.

Why is grep's -v unavailable? Does the implementation not provide it? If not, which platform are you on? I'm always curious about these situations.

Regards,
Alister
after all... what is 'grep'? And why is it called 'grep'? 'grep' is a glorified sed: sed 'g/re/p'.
# 6  
Old 10-20-2011
Quote:
Originally Posted by vgersh99
after all... what is 'grep'? And why is it called 'grep'? 'grep' is a glorified sed: sed 'g/re/p'.
Actually a glorified ed Smilie
# 7  
Old 10-20-2011
Except in that all three use regular expressions, I don't really see the relation... ed's capabilities are very different from both.

It's also horrifying. Smilie
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