Print line immediately before a matching regex.

awk '/regex/{print x};{x=$0}'
Use this if you don't have access to GNU grep's -B option.

By: res0nat0r
2009-06-26 19:29:54

What Others Think

Very similar to "grep -B1|head -n1"
alvieboy · 616 weeks and 5 days ago
I wish I had GNU grep on the Solaris systems I work on :(
res0nat0r · 616 weeks and 5 days ago
May almighty awk be with you then! ;)
alvieboy · 616 weeks and 5 days ago
Would someone be so kind as to explain which part shows the last line? This one-liner would really help me get data from logs and pipe it to a txt file for offline access. I tried changing things, but without understanding the parts after regex, I get mysterious results. I am new (well newish, been using, afraid of these commands for a while now) to linux/unix...Thanks so much!!
thagrasshoppa · 448 weeks ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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