Man pages › Compared with Linux and the BSDs

`command(1)` on Solnix vs Linux and the BSDs

On Solnix, command is the illumos /usr/bin/command utility, and the ksh93 shell also has a built-in command with extra options. The FreeBSD command(1) page is only an index of shell built-ins (builtin(1)). It lists command as a sh(1) built-in and documents no options, so FreeBSD behaviour cannot be compared flag by flag from the bundle.

The manual pages

Solnix: command(1) from pkgs.solnix.illumos-world-man · illumos.org
FreeBSD: command(1) 15.1-RELEASE
Standard: POSIX.1-2024 (IEEE Std 1003.1-2024), command

What Solnix runs

A default Solnix system runs the illumos /usr/bin/command. /usr/xpg4/bin/command is also shipped, but the bundle does not say how it differs. The page also describes a ksh93 built-in command, which adds -x and treats -v and -V as whence(1). No Linux page is in the bundle, so nothing is claimed about Linux.

Differences

Compared with	Topic	What differs
FreeBSD	what the page documents	The FreeBSD command(1) page is the builtin(1) index of csh(1) and sh(1) built-ins. It lists command but gives no synopsis, options, operands or exit status. Solnix documents `-p`, `-v`, `-V`, operands and exit codes. Source: FreeBSD command(1) NAME, SYNOPSIS, DESCRIPTION; Solnix command(1) SYNOPSIS, OPTIONS, EXIT STATUS
FreeBSD	which shells provide command	On FreeBSD, command is a built-in of sh(1) only; the table shows No for csh(1). Solnix ships both an external `/usr/bin/command` and a ksh93 built-in. The page does not say which shell is the default login shell. Source: FreeBSD command(1) Commands table (command: No*, csh No, sh Yes); Solnix command(1) SYNOPSIS (/usr/bin/command, ksh93)
FreeBSD	standalone utility	FreeBSD marks command as No: an external file exists, but it is a script that uses the shell built-in of the same name. Solnix `/usr/bin/command` is listed under its own SYNOPSIS, and `/usr/xpg4/bin/command` is also shipped. Source: FreeBSD command(1) Commands table and the 'No' note; Solnix command(1) SYNOPSIS
FreeBSD	`-x` option	Solnix ksh93 command `-x` reruns the command with subsets of the arguments if it fails for too many arguments. The exit status is the maximum of the invocations. `/usr/bin/command` has no `-x`, and the FreeBSD page documents no options. Source: Solnix command(1) ksh93 OPTIONS -x; Solnix command(1) /usr/bin/command SYNOPSIS; FreeBSD command(1) (no options)
FreeBSD	`-v` and `-V` in ksh93	In Solnix ksh93, command `-v` is equivalent to whence and command `-V` to whence `-v`. whence is not in the FreeBSD built-in table, so no FreeBSD equivalent is documented. Under `/usr/bin/command`, `-V` output format is unspecified. Source: Solnix command(1) ksh93 OPTIONS -v, -V; OPTIONS -V; FreeBSD command(1) Commands table
FreeBSD	`-p` search path	Solnix `/usr/bin/command` `-p` searches with a default PATH guaranteed to find all standard utilities. ksh93 `-p` searches 'a default path'. The FreeBSD page does not describe `-p`. Source: Solnix command(1) OPTIONS -p (both variants); FreeBSD command(1) (no options)
FreeBSD	exit status 126 and 127	Solnix returns 126 if the utility was found but could not be invoked, and 127 if it was not found or command itself failed. With `-v` or `-V`, any failure returns a value above 0. The FreeBSD page states no exit codes. Source: Solnix command(1) EXIT STATUS; FreeBSD command(1) (no EXIT STATUS)
FreeBSD	special built-ins	Solnix says command suppresses shell function lookup. For a special built-in, the special properties are removed; in ksh93 this means a failure does not terminate the calling script. The FreeBSD page says nothing about this. Source: Solnix command(1) DESCRIPTION (both variants); FreeBSD command(1) DESCRIPTION

Standards

POSIX: command is a POSIX.1-2024 utility.
Solnix: Interface Stability: Committed for /usr/bin/command. The Standard attribute says 'See standards(7)'.
FreeBSD: The FreeBSD page has no STANDARDS section for command in the bundle.

Writing portable scripts

Use only command -v name for existence checks and command name args to bypass functions. Both are documented on Solnix and are POSIX.1-2024. Check exit status, not output text.
Do not use command -x, and do not parse command -V output. -x exists only in Solnix ksh93, and the -V format is unspecified.

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.