mailwrapper(8) on Solnix vs Linux and the BSDs
On Solnix, mailwrapper is the illumos program at /usr/lib/mailwrapper. It replaces /usr/lib/sendmail and picks the MTA from /etc/mailer.conf. The BSDs describe the same program but install it as /usr/sbin/sendmail, and FreeBSD reads a second config file first.
The manual pages
- Solnix: mailwrapper(8) from
pkgs.solnix.illumos-world-man· illumos.org - FreeBSD: mailwrapper(8) 15.1-RELEASE
- OpenBSD: mailwrapper(8) 8.0
- NetBSD: mailwrapper(8) 11.0
What Solnix runs
A default Solnix system runs the illumos mailwrapper at /usr/lib/mailwrapper, not in /usr/bin, /usr/sbin or /sbin. No other variants are shipped. The page says its SYNOPSIS is 'Special. See below.' and gives no command-line options. Its configuration file is described in mailer.conf(5).
Differences
| Compared with | Topic | What differs |
|---|---|---|
| FreeBSD, OpenBSD, NetBSD | path of the sendmail replacement | Solnix mailwrapper replaces /usr/lib/sendmail. FreeBSD, OpenBSD and NetBSD pages say it replaces /usr/sbin/sendmail. Paths that MUAs or scripts hard-code for sendmail differ accordingly.Source: Solnix mailwrapper(8) DESCRIPTION; FreeBSD mailwrapper(8) DESCRIPTION; OpenBSD mailwrapper(8) DESCRIPTION; NetBSD mailwrapper(8) DESCRIPTION |
| FreeBSD | mailer.conf lookup order | FreeBSD reads ${LOCALBASE}/etc/mail/mailer.conf first, then falls back on /etc/mail/mailer.conf. Solnix names only /etc/mailer.conf.Source: FreeBSD mailwrapper(8) DESCRIPTION; Solnix mailwrapper(8) DESCRIPTION |
| OpenBSD, NetBSD | mailer.conf location | Solnix, OpenBSD and NetBSD all name /etc/mailer.conf as the configuration file, so the file location matches. The path of the wrapper binary does not.Source: Solnix, OpenBSD and NetBSD mailwrapper(8) DESCRIPTION |
| FreeBSD | periodic.conf side effect | The FreeBSD page says that if the replacement MTA does not support -A with mailq(1), daily_status_include_submit_mailq should be turned off in /etc/periodic.conf. The Solnix page only says other configuration files may need altering.Source: FreeBSD mailwrapper(8) DESCRIPTION, last paragraph; Solnix mailwrapper(8) DESCRIPTION, last paragraph |
| FreeBSD, OpenBSD, NetBSD | BUGS section | FreeBSD, OpenBSD and NetBSD pages have a BUGS section calling the program 'a crock' and asking for a standard way to submit mail. The Solnix page has no BUGS section. Source: FreeBSD, OpenBSD and NetBSD mailwrapper(8) BUGS; Solnix mailwrapper(8) (no BUGS) |
| OpenBSD | exit status documented | Solnix, FreeBSD and NetBSD document exit 0 on success and >0 on error. The OpenBSD page has no EXIT STATUS section. Source: Solnix, FreeBSD and NetBSD mailwrapper(8) EXIT STATUS; OpenBSD mailwrapper(8) (no EXIT STATUS) |
| FreeBSD, NetBSD | history | FreeBSD says mailwrapper first appeared in NetBSD 1.4 and then FreeBSD 4.0. NetBSD says it appeared in NetBSD 1.4. The Solnix and OpenBSD pages have no HISTORY section. Source: FreeBSD mailwrapper(8) HISTORY; NetBSD mailwrapper(8) HISTORY; Solnix mailwrapper(8) |
Standards
- POSIX: mailwrapper is not a POSIX.1-2024 utility.
Writing portable scripts
- Do not hard-code
/usr/sbin/sendmailor/usr/lib/sendmail.Look for the sendmail path on the system, since the wrapper is installed at/usr/lib/sendmailper the Solnix page and/usr/sbin/sendmailper the BSD pages.
Every difference here is taken from the manual pages linked above: Solnix's published page, Linux (man-pages and the GNU and util-linux manuals), FreeBSD, OpenBSD and NetBSD. Each row names its source. Where a manual is silent, this page is too. Compiled 2026-10-26. Found a mistake? Mail hackers@lists.solnix.io.