Postfix runs on AIX, BSD, HP-UX, IRIX, LINUX, MacOS X, Solaris, Tru64 UNIX, and other UNIX systems. It requires ANSI C, a POSIX.1 library, and BSD sockets. See below for the gory Details of what Postfix expects from the file system.
Gory details: the Postfix mail queue requires that (1) the file system can rename a file to a near-by directory without changing the file's inode number, and that (2) mail is safely stored after Fsync() of that file (not its parent directory) returns successfully, even when that file is renamed to a near-by directory at some later point in time. Maildir delivery also requires that (3) a file can be hard linked Between different near-by directories. Mailbox delivery introduces no additional requirements beyond what is already needed for Postfix queues.
Main features:
The following is a list of major Postfix features. Some features require third-party libraries (examples: LDAP, SQL, TLS). Other features are available only when the necessary operating system support exists and Postfix knows how to use it (examples: IP version 6, connection caching).
