sSMTP is a straightforward Mail Transport Agent (MTA) designed to send emails from a system to a mail hub.
One of the great things about sSMTP is that it is very straightforward. You can use the program to accept mail and send it to the mailhub, replacing the domain in the From: line with a different one if desired. However, it's important to note that sSMTP has some limitations--it won't receive mail, expand aliases, or manage a queue. These functions should be handled by a mailhub with an experienced system administrator.
The program is easy to install since it requires only a minimal amount of external configuration information. You can install it on a machine by copying the binary and an optional four-line config file. sSMTP supports Berkeley-derived systems, as well as those using /usr/lib/sendmail as a mail transfer agent. It has been used successfully on a variety of different systems, including SunOS 4.1.1, NextStep 2.x/3, and Ultrix 4.2. It has also been briefly tested on AIX 3.2 and RISCos, and has been used by others on DG U/X 5 and SVR4.
If you're using the Cygwin port of ssmtp, you may need to #define USE_OLD_ARPADATE (otherwise the day of the month will always be the letter "d"). Overall, sSMTP is a good choice for those looking for a simple and straightforward MTA that can handle their basic mail sending needs.
Version 2.62: N/A