Man pages › Compared with Linux and the BSDs

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

On Solnix, tsort is the illumos /usr/bin/tsort. It takes no options, only an optional file operand. FreeBSD has -d, -l and -q, and OpenBSD adds -f, -h, -r, -v and -w, so scripts that use those flags fail on Solnix.

The manual pages

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

What Solnix runs

A default Solnix system runs the illumos tsort at /usr/bin/tsort. No other variants are shipped. The Solnix page documents the SYNOPSIS `tsort [file]` and no options.

Differences

Compared with	Topic	What differs
FreeBSD, OpenBSD, NetBSD	`-q` and `-l` options	Solnix tsort has no options. FreeBSD and OpenBSD accept `-q` (suppress cycle messages) and `-l` (search for and display the longest cycle). A script that passes either flag will not work against the Solnix synopsis. The bundle has no NetBSD tsort page, so nothing is claimed for NetBSD. Source: Solnix tsort(1) SYNOPSIS; FreeBSD tsort(1) -l, -q; OpenBSD tsort(1) -l, -q
OpenBSD	OpenBSD-only options	OpenBSD has `-f`, `-h` file, `-r`, `-v` and `-w`. These cover tie-breaking order, a hints file, reversing the relation, reporting broken edges and exiting with the cycle count. None of them exists in the Solnix synopsis. Source: OpenBSD tsort(1) -f, -h, -r, -v, -w; Solnix tsort(1) SYNOPSIS
FreeBSD	`-d` debugging option	FreeBSD has `-d` to turn on debugging. Solnix tsort has no `-d`. Source: FreeBSD tsort(1) -d; Solnix tsort(1) SYNOPSIS
FreeBSD, OpenBSD	cycle handling	FreeBSD and OpenBSD ignore one arc in a cycle, continue the sort and report the cycle on standard error. The Solnix page does not describe what happens when the input contains a cycle. Source: FreeBSD tsort(1) DESCRIPTION; OpenBSD tsort(1) DESCRIPTION; Solnix tsort(1) DESCRIPTION
OpenBSD	exit status	Solnix and OpenBSD both document exit 0 on success and >0 on error. OpenBSD `-w` instead exits with the number of cycles broken. Solnix has no such option. Source: Solnix tsort(1) EXIT STATUS; OpenBSD tsort(1) EXIT STATUS, -w
Linux	stdin operand and options	Linux tsort reads standard input when FILE is omitted or is `-`, and has only `--help` and `--version`. Solnix says only that standard input is used when no file operand is given. The Solnix page does not mention `-` as an operand. Source: Linux tsort(1) DESCRIPTION, --help, --version; Solnix tsort(1) OPERANDS
FreeBSD, OpenBSD	input format	Solnix describes the input as pairs of items separated by blanks, where a pair of identical items marks presence only. FreeBSD and OpenBSD describe the same self-arc idea. They also require an even number of node names, which the Solnix page does not state. Source: Solnix tsort(1) DESCRIPTION; FreeBSD tsort(1) DESCRIPTION; OpenBSD tsort(1) DESCRIPTION
FreeBSD	multibyte characters	FreeBSD documents that tsort does not recognize multibyte characters. Solnix lists LANG, LC_ALL, LC_CTYPE, LC_MESSAGES and NLSPATH as affecting tsort. The Solnix page does not say how multibyte input is handled. Source: FreeBSD tsort(1) BUGS; Solnix tsort(1) ENVIRONMENT VARIABLES

Standards

POSIX: tsort is a POSIX.1-2024 utility.
Solnix: Interface Stability: Standard.
OpenBSD: The tsort utility is compliant with the IEEE Std 1003.1-2008 (“POSIX.1”) specification. The flags [-fhlqrvw] are extensions to that specification.

Writing portable scripts

Use only `tsort [file]` or read standard input in portable scripts. Leave out -q, -l, -d, -f, -h, -r, -v and -w, which are not in the Solnix synopsis.
Do not depend on how cycles are reported or what exit status results. The Solnix page does not specify cycle behaviour, and OpenBSD -w changes the exit status.

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.