Why check if file is exists in shell always false? - linux

Question

I created a cron using bash to delete files older than 3 days, but when checking the age of the files with mtime +3 &> /dev/null it is always false. here's the script:
now=$(date)
create log file
file_names=('*_takrib_golive.gz' '*_takrib_golive_filestore.tar.gz')
touch /media/nfs/backup/backup_delete.log
echo "Date: $now" >> /media/nfs/backup/backup_delete.log
for filename in "${file_names[#]}";
do
echo $filename
if ls /media/nfs/backup/${filename} &> /dev/null
then
echo "backup files exist"
if find /media/nfs/backup -maxdepth 1 -mtime +3 -name ${filename} -ls &> /dev/null
then
echo "The following backup file was deleted" >> /media/nfs/backup/backup_delete.log
find /media/nfs/backup -maxdepth 1 -mtime +3 -name ${filename} -delete
else
echo "There are no ${filename} files older than 3 days in /media/nfs/backup" &>> /media/nfs/backup/backup_delete.log
fi
else
echo "No ${filename} files found in /media/nfs/backup" >> /media/backup/backup_delete.log
fi
done
exit 0
in if find /media/nfs/backup -maxdepth 1 -mtime +3 -name ${filename} -ls &> /dev/null always goes to else, even though files older than 3 days are in the directory

Answer 1

You are not quoting the -name attribute so it expands to the name of the file which already exists.
I would refactor this rather extensively anyway. Don't parse ls output and perhaps simplify this by making it more obvious when to quote and when not to.
Untested, but hopefully vaguely useful still:
#!/bin/bash
backup=/media/nfs/backup
backuplog=$backup/backup_delete.log
# no need to touch if you write to the file anyway
date +"Date: %C" >> "$backuplog"
# Avoid using a variable, just loop over the stems
for stem in takrib_golive takrib_golive_filestore.tar
do
# echo $filename
# Avoid parsing ls; instead, loop over matches
for filename in "$backup"/*_"$stem".gz; do
pattern="*_$stem.gz"
if [ -e "$filename" ]; then
echo "backup files exist"
if files=$(find "$backup" -maxdepth 1 -mtime +3 -false -o -name "$pattern" -print -delete)
then
echo "The following backup file was deleted" >> "$backuplog"
echo "$files" >> "$backuplog"
else
echo "There are no $pattern files older than 3 days in $backup" >> "$backuplog"
fi
else
echo "No $pattern files found in $backup" >> "$backuplog"
fi
# Either way, we can break the loop after one iteration
break
done
done
# no need to explicitly exit 0
The for + if [ -e ... ] arrangement is slightly clumsy, but that's how you check if a wildcard matched any files. If the wildcard did not match, if [ -e will check for a file whose name is literally the wildcard expression itself, and fail.