Listing files that are older than one day in reverse order of modification time

In order to write a cleanup script on a directory, I need to take look at all files that are older than one day. Additionally, I need to delete them in reverse order of modification time (oldest first) until a specified size is reached.

I came along with the following approach to list the files:

find . -mtime +1 -exec ls -a1rt {} +

Am I right, that this does not work for a large number of files (since more than one 'ls' will be executed)? How can I achieve my goal in that case?

Solution

You can use the following command to find the 10 oldest files:

find . -mtime +1 -type f -printf '%T@ %p\n' | sort -n | head -10 | awk '{print $2}'

The steps used:

For each file returned by find, we print the modification timestamp along with the filename.
Then we numerically sort by the timestamp.
We take the 10 first.
We print only the filename part.

Later if you want to remove them, you can do the following:

rm $(...)

where ... is the command described above.