Linux Shell脚本如何使用相同的输出进行第二次操作

Question

This script has been create to backup files 24 hours before from now (midnight crontab), but my concern is, while the first tar is being created (first find) a lot of "" files are being created, so when the second find is executed, it would remove more files than the first one, so the removed files would be more than the backed up.

Script edited on February 4th 2014, focus on loop for removing the listed files on temp file

    #!/bin/sh
    DATE=`date '+%Y%m%d'`
    LOCATION=/home/see/rbirun/send/VPN/Mobile/
    FILE="cdr_backup_${DATE}.tar.gz"
    TEMPFILE="tempfile_${DATE}"
    ERROR="Error:Tar file not created nor removed the source call records"
    cd "${LOCATION}"
    find . -name 'VPN_CALLRECORD*' -type f -ctime 1 -print > ${TEMPFILE}
    tar -czf ${FILE} -T ${TEMPFILE}
    if [ -f $FILE ];
    then

            number=$(more ${TEMPFILE} |wc -l)
            echo "$DATE:Number of files backed up-->$number ">>log_after_cdr_backup.txt
            while IFS= read -r line
            do
                rm -f $line
            done < "${TEMPFILE}"
    else
            echo "$DATE:$ERROR">>log_after_cdr_backup.txt
    fi             

Is there a way to ensure that the same source backed up is removed ? maybe using 'xargs' ?

thanks in advance for your valuable help

Answer 1

如果您有足够的空间，请首先将找到的文件移动到工作文件夹中，然后在备份后删除该工作文件夹。

Answer 2

Your problem is you run find twice. Between the first invocation and the second anything could happen.

Do something like this instead:

#!/bin/sh
DATE=`date '+%Y%m%d'`
FILE="cdr_backup_${DATE}.tar.gz"
DESTINATION=/root/patrick_temp/
ERROR="Tar file has not been created nor removed the source call records"

BACKUP_FILES=$(find . -name 'VPN_CALLRECORD*' -type f -ctime 1 -print)
tar -czvf ${FILE} ${BACKUP_FILES}
if [ -f $FILE ];
then
    mv cdr_backup* ${DESTINATION}
    rm -rf ${BACKUP_FILES}
else
    echo $ERROR 
fi

If you might have LOTS of files to backup you can write the file names to a temp file, use that file for the tar invocation, and then use a loop to remove all of the files listed in the temp file.

EDIT based on your recent update.

#!/bin/sh
DATE=`date '+%Y%m%d'`
LOCATION=/home/see/rbirun/send/VPN/Mobile/
FILE="cdr_backup_${DATE}.tar.gz"
# use mktemp to make the temp file. This is more secure and better practice.
TEMPFILE=$(mktemp)  # --tmpdir lets you place the created temp file wherever you need it
ERROR="Error:Tar file not created nor removed the source call records"

cd "${LOCATION}"

find . -name 'VPN_CALLRECORD*' -type f -ctime 1 -print > ${TEMPFILE}

tar -czf ${FILE} -T ${TEMPFILE}

# first, cleanup temps

# no need for `more` here. Also, `cat` is more typically used when this is needed
number=$(wc -l ${TEMPFILE})  
echo "$DATE:Number of files backed up-->$number ">>log_after_cdr_backup.txt
for line in $(cat ${TEMPFILE})
do
    rm -f $line
done
rm ${TEMPFILE}

# now process activity

if [ ! -f $FILE ];
then
    echo "$DATE:$ERROR">>log_after_cdr_backup.txt
    exit 1
fi

I hope this settles your questions.