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How to delete all lines before a particular pattern when the pattern is defined in a variable?

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# 1  
Old 09-25-2017
How to delete all lines before a particular pattern when the pattern is defined in a variable?
I have a file

Code:
Line 1 a
Line 22
Line 33
Line 1 b
Line 22
Line 1 c
Line 4
Line 5

I want to delete all lines before last occurrence of a line which contains something which is defined in a variable. Say a variable var contains 'Line 1', then I need the following in the output.

Code:
Line 4
Line 5

# 2  
Old 09-25-2017
Code:
cat /dev/null >outfile
var="line 1"
while read line
do
   echo "$line" >>outfile
   if [ "$var" = "$line" ]
       then
       cat /dev/null >outfile
   fi
done <inputfile

This User Gave Thanks to jgt For This Post:
drl
# 3  
Old 09-25-2017
Thx.. But this will not work. Lines are not just 'Line 1'. They contains some more text a;so. And I need to delete all lines before the last occurrence.

I could not construct a simple sed or awk script.
# 4  
Old 09-25-2017
Hi,
with your example file:
Code:
$ cat /tmp/bob2 
Line 1 a
Line 22
Line 33
Line 1 b
Line 22
Line 1 c
Line 4
Line 5
$ XX="Line 1"
$ awk -vRS="$XX(\n| [^\n]+\n)" -vORS="" 'END{print}' /tmp/bob2
Line 4
Line 5
$ XX="Line 2"
$ awk -vRS="$XX(\n| [^\n]+\n)" -vORS="" 'END{print}' /tmp/bob2
Line 1 a
Line 22
Line 33
Line 1 b
Line 22
Line 1 c
Line 4
Line 5
$ XX="Line 22"
$ awk -vRS="$XX(\n| [^\n]+\n)" -vORS="" 'END{print}' /tmp/bob2
Line 1 c
Line 4
Line 5

Regards.
# 5  
Old 09-25-2017
I tried this but I am not getting any output !! FYI, I am using ksh. I tried sh also but the same result.
# 6  
Old 09-25-2017
There's far better ways to put variables in awk than that, and cramming it into RS is liable to produce gigantic records that will be truncated.

Code:
PAT="Line 1"
awk 'NR==FNR { if(match($0, PAT)) P=NR ; next } FNR > P' PAT="Line 1" inputfile inputfile

Note that the input file is given twice, once to find the last pattern, the second time to print everything after it.

If this doesn't work for you, please show exactly how you used it, word for word, letter for letter, keystroke for keystroke.
# 7  
Old 09-25-2017
Now some compilation error

Code:
ksh: cat e
Line 1
Line 22
Line 33
Line 1
Line 22
Line 1
Line 4
Line 5
ksh:
ksh: PAT="Line 1"
ksh: awk 'NR==FNR { if(match($0, PAT)) P=NR ; next } FNR > P' PAT="Line 1" e e
awk: syntax error near line 1
awk: illegal statement near line 1
ksh:
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