This can actually relate to SMTP servers using mbox or maildir formats. Maildir is more resistant to corruption, and doesn't rely (as much) on file locks. http

This can actually relate to SMTP servers using mbox or maildir formats. Maildir is more resistant to corruption, and doesn't rely (as much) on file locks. https://serverfault.com/questions/564456/what-are-the-practical-differences-between-maildir-and-mbox https://serverfault.com/questions/564456/what-are-the-practi...