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read file backwards


 
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# 1  
Old 09-28-2007
read file backwards

Assume file1 contains a list of strings.
My first script is scanning the file and deals with the lines with a certain patern in it:

grep 'somepatern' file1 \
while read LINE ; do
doSomethingAboutIt
done

Now, I need a second script that deals with the same lines (& do something differently) but in the opposite order; the last line found in the file with that patern shuld be handled first.

Please help me. Thanks so much!!!

Last edited by bluemoon1; 09-28-2007 at 01:36 AM.. Reason: typo
# 2  
Old 09-28-2007
You could generate a file with all the lines reversed by using something like

Code:
cat </dev/null >output
while read N
do
     echo "$N" >output.tmp
     cat output >>output.tmp
     mv output.tmp output
done

# 3  
Old 09-28-2007
Hey, there's a new approach. For some other solutions see: sort a file in reverse order
# 4  
Old 09-28-2007
Thanks you so much, Porter & Perderabo!!
Yes, this will do (& is cute too;-)
tail -r file1

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