Man pages › Compared with Linux and the BSDs

`unshare(8)` on Solnix vs Linux and the BSDs

Solnix unshare(8) is the illumos /usr/sbin/unshare, which stops sharing a local file system resource so remote clients can no longer mount it. Linux unshare(1) is an unrelated command that runs a program in new namespaces, so the two share only a name.

The manual pages

Solnix: unshare(8) from pkgs.solnix.illumos-world-man · illumos.org
Linux: unshare(1) util-linux-2.42.3

What Solnix runs

A default Solnix system runs the illumos unshare at /usr/sbin/unshare. No other variants are shipped. Its companion is share(8), and shareall(8) is also listed. The bundle has no FreeBSD, OpenBSD or NetBSD unshare page, so nothing is compared with the BSDs.

Differences

Compared with	Topic	What differs
Linux	purpose	Solnix unshare(8) removes a shared local resource from NFS-style sharing. Linux unshare(1) creates new namespaces (mount, UTS, IPC, network, PID, cgroup, user, time) and then runs a program in them. The commands are not interchangeable. Source: Solnix unshare(8) NAME, DESCRIPTION; Linux unshare(1) NAME, DESCRIPTION
Linux	synopsis and arguments	Solnix takes an optional pathname or resourcename to stop sharing. Linux takes namespace options followed by a program and its arguments. If no program is given, Linux runs ${SHELL}, default `/bin/sh.` Source: Solnix unshare(8) SYNOPSIS; Linux unshare(1) SYNOPSIS, DESCRIPTION
Linux	`-p` meaning	Solnix unshare `-p` removes the resource from shared status persistently across reboots. Linux unshare `-p` (`--pid`[=file]) creates a new PID namespace. A Linux script using `-p` does something unrelated on Solnix. Source: Solnix unshare(8) -p; Linux unshare(1) -p, --pid
Linux	`-o` meaning and `-F`	Solnix `-o` passes file-system-specific options and `-F` FSType selects the file system type. Linux `-o` is not documented in the extracted text here, and Linux has no `-F` option in the flag list. Linux `-f` is `--fork`, not a file system type. Source: Solnix unshare(8) -F, -o; Linux unshare(1) option list, -f, --fork
Linux	default file system type	If `-F` is omitted, Solnix uses the first file system type listed in `/etc/dfs/fstypes.` Linux unshare(1) has no file system type concept and does not mention this file. Source: Solnix unshare(8) DESCRIPTION; Linux unshare(1) DESCRIPTION
Linux	error handling	On Solnix, if the pathname or resourcename is not in the shared information, an error message goes to standard error. The extracted Linux text does not describe an equivalent case. Source: Solnix unshare(8) NOTES; Linux unshare(1) DESCRIPTION
Linux	effect on remote clients	A successful Solnix unshare means a client that was mounting the file system no longer has access to it. Linux unshare only changes which namespaces the new process lives in. It does not affect remote clients. Source: Solnix unshare(8) NOTES; Linux unshare(1) DESCRIPTION
Linux	privilege and persistence model	Linux unshare namespaces last only while they have member processes, unless made persistent by bind mounting `/proc/pid/ns/type` files. Solnix uses `-p` to make the removal of sharing persistent across reboots. Source: Linux unshare(1) DESCRIPTION; Solnix unshare(8) -p

Standards

POSIX: unshare is not a POSIX.1-2024 utility.
Solnix: The page SEE ALSO references attributes(7); the extracted text shows no ATTRIBUTES or stability table.

Writing portable scripts

Do not call unshare by name in cross-platform scripts: it stops file system sharing on Solnix and creates namespaces on Linux. Test for the OS first.
On Solnix, use share(8) and unshare(8). Do not assume the Linux -p, -o or -f meanings.

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.