Man pages › Compared with Linux and the BSDs

`mail(1b)` on Solnix vs Linux and the BSDs

On a default Solnix system /usr/bin/mail is the illumos mail. The mail(1b) page covers only /usr/ucb/mail and /usr/ucb/Mail, which are links to /usr/bin/mailx. The page documents no options, so for usage you must read mailx(1). Linux and the BSDs document mail as the full mail client.

The manual pages

Solnix: mail(1b) from pkgs.solnix.illumos-world-man · illumos.org
Linux: mail(1) mailutils-3.21
FreeBSD: mail(1) 15.1-RELEASE
OpenBSD: mail(1) 8.0
NetBSD: mail(1) 11.0

What Solnix runs

The published page is mail(1b), which describes /usr/ucb/mail and /usr/ucb/Mail as links to /usr/bin/mailx. The header says the command on PATH is /usr/bin/mail, and the bundle does not describe that program. See mailx(1) for usage. The page lists no options, so any flag comparison below rests on the counterpart pages only.

Differences

Compared with	Topic	What differs
all four	where the options are documented	The Solnix mail(1b) page has no options section and refers to mailx(1) for usage. Linux, FreeBSD, OpenBSD and NetBSD document mail, its options and its commands on the mail page itself, so you cannot compare flags from the Solnix page alone. Source: Solnix mail(1b) DESCRIPTION; FreeBSD mail(1) SYNOPSIS; OpenBSD mail(1) DESCRIPTION; NetBSD mail(1) DESCRIPTION
FreeBSD, OpenBSD, NetBSD	mail is a link to mailx	Solnix documents `/usr/ucb/mail` and `/usr/ucb/Mail` as links to `/usr/bin/mailx.` The BSD pages name mail, Mail and mailx together as one program. FreeBSD's BUGS section notes that mail is usually a link to Mail and mailx. Source: Solnix mail(1b) DESCRIPTION; FreeBSD mail(1) NAME, BUGS; OpenBSD mail(1) NAME; NetBSD mail(1) NAME
Linux	different program on Linux	The Linux page is for GNU Mailutils mail, whose synopsis is mail [OPTION...] [address...]. The page lists no options and points to the Texinfo manual (info mail). Behaviour cannot be compared with Solnix from these texts. Source: Linux mail(1) NAME, SYNOPSIS, SEE ALSO; Solnix mail(1b) DESCRIPTION
FreeBSD, OpenBSD, NetBSD	`-E` empty messages	FreeBSD, OpenBSD and NetBSD list `-E`. OpenBSD and NetBSD say it stops messages with an empty body from being sent. The Solnix page documents no `-E`; check mailx(1). Source: OpenBSD mail(1) -E; NetBSD mail(1) -E; FreeBSD mail(1) SYNOPSIS; Solnix mail(1b) DESCRIPTION
OpenBSD, NetBSD	`-r` meaning differs between the BSDs	On OpenBSD, `-r` from-addr sets the From address of the message and envelope. On NetBSD, `-r` names an alternate rc file overriding MAILRC. The Solnix page does not document `-r`. Do not assume it is portable. Source: OpenBSD mail(1) -r; NetBSD mail(1) -r; Solnix mail(1b) DESCRIPTION
NetBSD	`-a` and `-H`	NetBSD mail has `-a` file to attach a file and `-H` to print header summaries and exit. FreeBSD lists `-H` in its synopsis but the bundle excerpt has no OPTIONS text for it. The Solnix page documents neither flag. Source: NetBSD mail(1) -a, -H; FreeBSD mail(1) SYNOPSIS; Solnix mail(1b) DESCRIPTION
NetBSD	options after recipients	On NetBSD, flags after the recipient list are passed to sendmail, for example mail recipient `-f` somebody@somewhere.net. FreeBSD's synopsis also allows [`-sendmail-option` ...] after to-addr. The Solnix page says nothing about this. Source: NetBSD mail(1) Sending mail; FreeBSD mail(1) SYNOPSIS; Solnix mail(1b) DESCRIPTION
FreeBSD	environment variables	FreeBSD mail documents DEAD (default ~/dead.letter), MAIL (default `/var/mail`), MAILRC (default ~/.mailrc), MBOX, LISTER, PAGER, REPLYTO and others. The Solnix mail(1b) page documents no environment variables. Source: FreeBSD mail(1) ENVIRONMENT; Solnix mail(1b) DESCRIPTION
OpenBSD, NetBSD	startup file	OpenBSD and NetBSD read `/etc/mail.rc` at startup unless `-n` is given, then ~/.mailrc. The Solnix mail(1b) page does not describe startup files. Source: OpenBSD mail(1) Startup actions, -n; NetBSD mail(1) -n; Solnix mail(1b) DESCRIPTION

Standards

POSIX: mail is not a POSIX.1-2024 utility.
Solnix: The mail(1b) page lists attributes(7) under SEE ALSO. The excerpt in the bundle has no interface stability table.
FreeBSD: HISTORY: a mail command appeared in Version 1 AT&T UNIX. The page is derived from The Mail Reference Manual by Kurt Shoens.

Writing portable scripts

Do not rely on mail options beyond -s and a recipient list in portable scripts. -r, -a, -H and -E differ or are missing across the systems.
On Solnix, read mailx(1) for the real option list. /usr/bin/mail and /usr/ucb/mail are different paths, and the bundle does not describe /usr/bin/mail.

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.