| Feature | Explanation |
|---|---|
| define(`confEBINDIR', `/usr/local/libexec') FEATURE(smrsh) | Use smrsh (the sendmail restricted shell) instead of /bin/sh for program delivery. This is usually done for security reasons, since smrsh allows you to restrict which programs are run by users. The smrsh binary is installed in the directory specified by the confEBINDIR variable. |
| FEATURE(local_procmail) | If you have procmail installed, I highly recommend that you use it for your local MDA. procmail is both an extremely flexible and useful tool for users to filter their incoming mail, but it also serves as an excellent cross-platform standard MDA for heterogeneous environments. |
| define(`confCW_FILE', `-o /etc/mail/local-host-names') FEATURE(use_cw_file) | Normally, sendmail will assume that only mail addressed to your hostname should be delivered locally, and that other mail should be forwarded to the destination address. If you use this feature, you can create a file called /etc/mail/local-host-names (the path can be changed via the confCW_FILE define, as shown) which contains a list of other destination addresses which should be considered local. |
| FEATURE(no_default_msa) | Starting in version 8.10, sendmail listens on port 587 port to support MSA (Mail Submission Agent). This is intended to be used by POP/IMAP clients such as Eudora instead of the "SMTP Server" setting they use today. Currently, there aren't many clients which support MSA, but it is expected that support for this will increase over time. |
