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.
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).
By popular demand...
Junk mail control