Get previous and next line


 
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# 1  
Old 09-15-2009
Get previous and next line

I'm trying to figure out how to do this I need to search for pattern when found the previous line and next line should be captured if in case the next or previous line is also matching move to one step previous or ahead.
Also need to search for a pattern and exit once the 3rd occurence is being found.

Tried using awk and using getline function to get previous but couldnt get next line.Any variant of awk, sed or perl is appreciated.
# 2  
Old 09-15-2009
please give your input file for better solution(and tell how you want to figure it out).
# 3  
Old 09-15-2009
The pattern is ABC in below file.
Code:
ABC
NEW
ABC
ABC
NEW
OP
ABC

# 4  
Old 09-15-2009
And.. what's the required output for your example?
# 5  
Old 09-15-2009
search for ABC if its found its previous line and next line should be displayed if the next or previous line is same then its further next or previous line.
# 6  
Old 09-15-2009
How about:

Code:
grep -A1 -B1 "some_string"

# 7  
Old 09-15-2009
Sorry but I don't really get it. Post a sample output based on you example to illustrate your request. Much easier to understand when provided with input *and* output samples.
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