Postfix Local Mail
The goal of this article is to setup Postfix for local mailbox delivery only. See: Postfix for a virtual mail delivery configuration.
Step 1: Edit /etc/postfix/main.cf
The only things you need to change are as follows. Uncomment them and modify them to the specifics listed below. Everything else can be left as installed by pacman.
inet_interfaces = loopback-only mynetworks_style = host append_dot_mydomain = no default_transport = error: Local delivery only!
If you want to control where the mail gets delivered and which mailbox format is to be used, you can do this by setting
home_mailbox = /some/path
mail_spool_directory is an absolute path where all mail goes, while home_mailbox specifies a mailbox relative to the user's home directory. If the path ends with a slash ('/'), messages are stored in Maildir format (directory tree, one message per file); if it doesn't, the mbox format is used (all mail in one file).
mail_spool_directory = /var/mail (1) home_mailbox = Maildir/ (2)
1) All mail will be stored in /var/mail, mbox format
2) Mail will be saved in ~/Maildir, Maildir format