Man pages › Compared with Linux and the BSDs

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

On a default Solnix system chgrp is the illumos /usr/bin/chgrp. It has no -v, no --reference and no -c, which Linux and the BSDs provide, and it adds -s to set a group by Windows SID.

The manual pages

Solnix: chgrp(1) from pkgs.solnix.illumos-world-man · illumos.org
Linux: chgrp(1) coreutils-full-9.11
FreeBSD: chgrp(1) 15.1-RELEASE
OpenBSD: chgrp(1) 8.0
NetBSD: chgrp(1) 11.0
Standard: POSIX.1-2024 (IEEE Std 1003.1-2024), chgrp

What Solnix runs

/usr/bin/chgrp is the illumos chgrp. /usr/xpg4/bin/chgrp is also shipped. The Solnix page says the two once behaved differently and now behave the same way.

Differences

Compared with	Topic	What differs
Linux, FreeBSD, NetBSD	`-v` verbose	Solnix chgrp has no `-v`. Linux, FreeBSD and NetBSD accept `-v` to report each file processed. FreeBSD marks `-v` as non-standard and not recommended in scripts. OpenBSD has no `-v` either. Source: Solnix chgrp(1) OPTIONS; Linux chgrp(1) -v; FreeBSD chgrp(1) -v, COMPATIBILITY; NetBSD chgrp(1) -v
Linux	`-c` and `--reference`	Solnix chgrp has no `-c` (report only changes) and no `--reference=RFILE`. Linux has both. A Linux script copying the group from a reference file fails on Solnix. Source: Linux chgrp(1) -c, --reference; Solnix chgrp(1) SYNOPSIS
NetBSD	`--reference` and `-d`	NetBSD chgrp accepts `--reference=rfile` and `-d` (skip the update if the group is already the desired value). Solnix has neither. Source: NetBSD chgrp(1) SYNOPSIS, -d; Solnix chgrp(1) SYNOPSIS
all four	`-s` Windows SID	Solnix `-s` treats the group operand as a Windows SID and needs a file system that stores SIDs, such as ZFS. None of the counterpart pages document `-s`. Source: Solnix chgrp(1) -s, SYNOPSIS; Linux, FreeBSD, OpenBSD, NetBSD chgrp(1) OPTIONS
FreeBSD	`-x` mount points	FreeBSD `-x` stops traversal at file system mount points, and the page calls it non-standard. Solnix chgrp has no `-x`. Source: FreeBSD chgrp(1) -x, COMPATIBILITY; Solnix chgrp(1) SYNOPSIS
OpenBSD	`-h` with `-R`, and `-f`	OpenBSD says `-h` and `-R` are mutually exclusive, and it has no `-f`. Solnix accepts `-f` and `-h` and `-R` together in its synopsis, and `-f` suppresses error reports. Source: OpenBSD chgrp(1) SYNOPSIS, -h; Solnix chgrp(1) SYNOPSIS, -f
all four	`-H`/-L/-P without `-R`	Solnix describes `-H`, `-L` and `-P` as acting on symbolic links given on the command line even though `-R` is the recursion option, and the last of them wins. Linux, FreeBSD, OpenBSD and NetBSD say they take effect only with `-R`. For Solnix the manual says `-R` defaults to `-P`. Source: Solnix chgrp(1) -H, -L, -P, -R; Linux chgrp(1) DESCRIPTION; FreeBSD chgrp(1); OpenBSD chgrp(1); NetBSD chgrp(1)
all four	symlink default without `-h`	Solnix without `-h` changes the group of the file a symlink references. Linux calls this the default (`--dereference`). NetBSD says chgrp on a symlink without `-h` has no effect and succeeds unless `-H` or `-L` is set. Source: Solnix chgrp(1) -h; Linux chgrp(1) --dereference; NetBSD chgrp(1) DESCRIPTION
NetBSD	numeric group names	NetBSD looks up the group name first and lets you force a number with a leading #. Solnix uses the numeric ID if the number is found in the group database as a name, and does not document #. Source: NetBSD chgrp(1) group operand, STANDARDS; Solnix chgrp(1) OPERANDS
all four	ownership restriction	Solnix documents _POSIX_CHOWN_RESTRICTED, on by default and controlled by set rstchown in `/etc/system.` Without privilege, the owner can change the group only to one they belong to. The BSD pages state the same rule without the setting. The Linux page is silent. Source: Solnix chgrp(1) DESCRIPTION; FreeBSD, OpenBSD, NetBSD chgrp(1); Linux chgrp(1)

Standards

POSIX: chgrp is a POSIX.1-2024 utility.
Solnix: Interface Stability: Committed. Standard: see standards(7). CSI-enabled except for the group name.
FreeBSD: Expected to be IEEE Std 1003.2 (“POSIX.2”) compatible. -v and -x are non-standard.
OpenBSD: The chgrp utility is compliant with the specification.
NetBSD: Expected to be POSIX 1003.2 compatible. -v, -d and the use of # to force a numeric group ID are extensions to IEEE Std 1003.2 (“POSIX.2”).

Writing portable scripts

Use only chgrp [-fhR] [-H|-L|-P] group file. Avoid -v, -c, -d, -x, -s and --reference; they are missing on at least one system.
Do not combine -h with -R; OpenBSD documents them as mutually exclusive.

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.