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awk - last instance of a string

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# 1  
Old 04-07-2011
awk - last instance of a string
How do I use awk to find the last occurence of a string in a file?
Last edited by locoroco; 04-07-2011 at 04:55 PM..
# 2  
Old 04-07-2011
Code:
grep string file | tail -1

If you insist on using awk:
Code:
awk '/string/{a=$0}END{print a}' file

This User Gave Thanks to mirni For This Post:
locoroco
# 3  
Old 04-07-2011
Quote:
Originally Posted by mirni
Code:
grep string file | tail -1

If you insist on using awk:
Code:
awk '/string/{a=$0}END{print a}' file

Hi, mirni:

To match an arbitrary string, it's best to stay away from regular expression syntax, since the string could include metacharacters. Tweaking your code slightly:

Code:
grep -F string file | tail -n1

Code:
awk -v s=string 'index(s, $0) {a=$0} END {print a}' file

Regards,
Alister
These 2 Users Gave Thanks to alister For This Post:
locoroco mirni
# 4  
Old 04-07-2011
Code:
$ tac file  | grep -m1 string

This User Gave Thanks to kurumi For This Post:
locoroco
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