E-mail file, copy it with the current date appended to the filename and empty the file contents.

mail-and-rotate.sh

#!/bin/bash

FILE=targetfile.txt

echo "Email body text goes here" | mutt -a "$FILE" -s "Email subject goes here" -- [email protected]

TIMESTAMP=`date +%Y%m%d`
NEW_FILE=$FILE.$TIMESTAMP
cp $FILE $NEW_FILE

/dev/null > $FILE