I want to create a folder for users to put their temporary files and a folder for users to put their permanent files. For the temporary folder, I need to implement a deletion policy. I would like to know normally which time, ctime, mtime or atime, should be used to implement such deletion policy.
We use "mtime" (the same timestamp as "ls -la").
I fact there is little use for the "atime" or "ctime" timestamps because they are liable to be changed by drive-through processes such as people browsing or backup software.