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Finding a flatfile & deleting first line


 
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# 1  
Old 07-21-2009
Finding a flatfile & deleting first line

I have a small script where I want to see if a file exists & then delete the first line from it.

I have code to help me find if the file exists, but I am unsure as to how to then take in the answer and remove the first line from the flatfile:

This is what I have so far just to output if the file exists:

for a in $(cat ~/scripts/test.txt)
do

if [ -f $DEST/$a ]
then
echo file $a exists >> ~/scripts/test2.txt
else
echo file $a does not exist >> ~/scripts/test3.txt
fi
done
# 2  
Old 07-21-2009
You can take the 2nd to last line of the file with below command

Code:
sed -n '2,$ p' filename

# 3  
Old 07-21-2009
the problem is that I don't know how I can do sed to remove a line when the file name is only specified by "-f $DEST/$a" as I don't know how to put that into a variable.
# 4  
Old 07-21-2009
I have added the sed statement in your script

Code:
for a in $(cat ~/scripts/test.txt)
do

if [ -f $DEST/$a ]
then
echo file $a exists >> ~/scripts/test2.txt
sed -n '2,$ p' $DEST/$a > $DEST/$a.tmp
mv $DEST/$a.tmp $DEST/$a
else
echo file $a does not exist >> ~/scripts/test3.txt
fi
done


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