Building Cone

Cone is distributed in source code form, licensed under GPL. See COPYING for more information. The following prerequisites must be installed to build and run Cone:

Right now the primary development focus is on the Linux platform, but Cone should build on other POSIX platforms; and any problems are likely to be minor, and trivial to resolve. A large portion of Cone's code base comes from Courier, which builds on many platforms.


Cone requires a wide-character-capable version of Curses. Cone will compile against a non-widechar Curses, but will not be able to display UTF-8, or other variable-length character sets.

Reading local mail with Cone

Cone reads local mail from either maildirs (the preferred format) or mailbox files (or "mboxes"). When mboxes are used, Cone does not read the system mailbox file directly (usually /var/spool/something). All messages in the system mailbox are automatically moved to $HOME/Inbox, which is then accessed as if it was the system mailbox. Starting Cone for the first time on an mbox-based system automatically copies all existing mail from the system mailbox file to $HOME/Inbox.

This is an intentional design choice. Normal user application cannot create new files in /var/spool; all they can do is read the mailbox file from /var/spool. Therefore, the only way to update the mailbox file is by rewriting it from scratch (more or less). While the mailbox file is in the process of being rewritten, if the Cone process is interrupted, or killed, the resulted in a corrupted system mailbox. There are way to minimize this vulnerability, but it cannot be eliminated completely. Some Linux kernels use an OOM killer that may terminate any process when the system memory is low. There is no way to completely prevent corrupted system mailbox files on those kernels.

Cone uses an alternative way of updating mboxes. Cone updates mboxes by creating a new mbox file separately, then replacing the original mbox file with the new version. Unfortunately this cannot be done with the system mailbox file, because of the restricted access rights on the system spool directory. To solve this problem Cone automatically copies the system mailbox file to $HOME/Inbox, each time the system mailbox file is opened and whenever new mail is available.