Originally Posted by JeremyBoden
It was caused by the use of the directory separator character '/' in a name.
Hello Jeremy, I don't get your idea
But I found out the magic beyond this folder. '.ckpt' means checkpoint. The '.ckpt' directory belongs to network storage which provide a feature called checkpoint(NAS/SAN/Others). In Linux system, we cannot issue 'ls -a' command to view it but we need to specify it explicitly.
The purpose of this folder is to offer the backup method which preventing accidental deletion of files/folders. It is something like shadow copy on Windows system.
I have just got the idea beyond this, still not implement it.