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I need to calculate the md5sum of one string per line in my ls dump:

directory_listing.txt:

./r/g4/f1.JPG
./r/g4/f2.JPG
./r/g4/f3.JPG
./r/g4/f4.JPG

However the md5sum should be calculated without the 'first dot'. I've written a simple script so far:

while read line
do
echo $line | exec 'md5sum'
done

./g.sh < directory_listing.txt

How can I remove the first dot from each line?

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Why not just generate the file without it in the first place? – Ignacio Vazquez-Abrams Jul 6 '11 at 9:08
    
that file was not generated by me, so i cant. – JosiP Jul 6 '11 at 9:09
    
exec isn't doing anything useful here -- just use echo "${line#./}" | md5sum. – Gordon Davisson Jul 6 '11 at 14:36
$ foo=./abc/123
$ echo "${foo#./}"
abc/123
share|improve this answer

Change:

echo $line | exec 'md5sum'

to:

echo $line | cut -c 2- | exec 'md5sum'
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