maildir

TLDR

Create Maildir structure

$ mkdir -p [~/Maildir]/{cur,new,tmp}

List new messages

$ ls [~/Maildir/new/]

Move message to read

$ mv [~/Maildir/new/message] [~/Maildir/cur/]

Check Maildir permissions

$ ls -la [~/Maildir/]

SYNOPSIS

Maildir/ - Directory-based email storage format

Maildir is a mail storage format where each email is stored as a separate file in a directory structure. It consists of three subdirectories: cur (read), new (unread), and tmp (in-progress delivery).
Maildir avoids file locking issues of mbox format and allows concurrent access from multiple programs.

DIRECTORY STRUCTURE

$ Maildir/
├── cur/     # Read messages
├── new/     # Unread messages
├── tmp/     # Temporary (delivery)
└── .Folder/ # Subfolders (ISTRSTRSTRSTRSTRSTRSTRSTRSTRSTRSTR
    ├── cur/
    ├── new/
    └── tmp/

FILE NAMING

$ # Format: time.pid.hostname:2,flags
1234567890.12345.hostname:2,S

Flags: S=Seen, R=Replied, F=Flagged, T=Trashed, D=Draft

CAVEATS

More files than mbox. Filesystem must support many small files. Some tools expect specific naming. Subfolders prefixed with dot.

HISTORY

Maildir was developed by Daniel J. Bernstein for his qmail MTA in 1995 as a reliable alternative to the traditional mbox format.