openssl x509 -in server.pem -noout -fingerprint

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Move all files over a day old into the tempdir directory:

find . -mtime +1 -print | xargs -t -i mv {} tempdir


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Gzip and tar all files over a day old into one archive:

find . -mtime +1 -print | tar cvzf archive.tar.gz


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# find all duplicate folders (the "#" is in place of the normal "/" field separator):

find ~/graphics/ | sed s#.*/##g | sort | uniq --repeated | grep -iv .jpg


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# find all folders with a space in the name:

find ~//graphics/ | sed s#.*/##g | grep -iv .jpg | grep " "


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# Find lines in several text files

find . -name *.txt -exec grep -Hn "SEARCH_STRING" {} \;
 or
grep -Hnsr "STRING" .*txt


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# Script to search and replace recursively

#!/bin/sh

if [ $# -lt 3 ] ; then
echo -e "Wrong number of parameters."
echo -e "Usage:"
echo -e " renall 'filepat' findstring replacestring\n"
exit 1
fi

#echo $1 $2 $3
for i in `find . -name "$1" -exec grep -l "$2" {} \;`
do
mv "$i" "$i.sedsave"
sed "s/$2/$3/g" "$i.sedsave" > "$i"
echo $i
#rm "$i.sedsave"
done