Man pages › Compared with Linux and the BSDs

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

On Solnix, lastcomm is the illumos lastcomm at /usr/bin/lastcomm. It can read standard or extended process accounting files, and has -x for the active extended accounting file. It lacks the FreeBSD -E/-S/-c/-e/-s/-u and +format options and the NetBSD -w option.

The manual pages

Solnix: lastcomm(1) from pkgs.solnix.illumos-world-man · illumos.org
FreeBSD: lastcomm(1) 15.1-RELEASE
OpenBSD: lastcomm(1) 8.0
NetBSD: lastcomm(1) 11.0

What Solnix runs

A default Solnix system runs the illumos lastcomm at /usr/bin/lastcomm. No other variants are shipped. Extended process accounting is managed with acctadm(8); the Solnix page does not say how to turn standard accounting on.

Differences

Compared with	Topic	What differs
FreeBSD, OpenBSD, NetBSD	`-x` and extended accounting	Solnix lastcomm `-x` reads the currently active extended process accounting file, and produces no output if extended accounting is inactive. The FreeBSD, OpenBSD and NetBSD pages document no `-x` and no extended accounting source. Source: Solnix lastcomm(1) -x, DESCRIPTION (acctadm(8)); FreeBSD/OpenBSD/NetBSD lastcomm(1) SYNOPSIS
FreeBSD, OpenBSD, NetBSD	`-f` file formats	Solnix `-f` accepts either an extended or a standard process accounting file. The BSD pages say only that `-f` reads from a file instead of the default accounting file. Source: Solnix lastcomm(1) -f; FreeBSD/OpenBSD/NetBSD lastcomm(1) -f
FreeBSD	output selection options and default	FreeBSD lastcomm has `-E`, `-S`, `-c`, `-e`, `-s` and `-u` to choose which times are printed, and assumes `-cS` if none is given. Solnix has none of these and always prints CPU time and exit date and time. Source: FreeBSD lastcomm(1) -E, -S, -c, -e, -s, -u; Solnix lastcomm(1) SYNOPSIS, DESCRIPTION (items per entry)
FreeBSD	+format and stdin	FreeBSD accepts a +format strftime(3) operand and `-f` - to read entries from standard input. The Solnix page documents neither. Source: FreeBSD lastcomm(1) DESCRIPTION (+format), -f; Solnix lastcomm(1) SYNOPSIS
FreeBSD, OpenBSD, NetBSD	time shown	Solnix prints the date and time the process exited. OpenBSD and NetBSD print the start time and elapsed time. FreeBSD prints start time by default (`-cS`) and exit time only with `-E`. Source: Solnix lastcomm(1) DESCRIPTION (last item); OpenBSD/NetBSD lastcomm(1) DESCRIPTION; FreeBSD lastcomm(1) -E, -S
FreeBSD, OpenBSD, NetBSD	column order	Solnix lists command name first, then flags, user, terminal, CPU time and exit time. The BSD pages list the user first, then flags, then the command name. Source: Solnix lastcomm(1) DESCRIPTION (item list); FreeBSD/OpenBSD/NetBSD lastcomm(1) DESCRIPTION (item list)
FreeBSD, OpenBSD, NetBSD	flag S meaning	On Solnix, S means the process ran as a set-user-id program. On FreeBSD and NetBSD, S means the command was executed by the super-user. On OpenBSD, S means a system call from the wrong instruction. Source: Solnix lastcomm(1) flags S; FreeBSD/NetBSD lastcomm(1) flags; OpenBSD lastcomm(1) flags S
FreeBSD, OpenBSD, NetBSD	other flags	Solnix documents only F and S. FreeBSD, OpenBSD and NetBSD also document D (core file) and X (killed by signal). OpenBSD adds B, M, P, T and U; NetBSD adds C. Do not expect these flags on Solnix. Source: Solnix lastcomm(1) flags; FreeBSD/OpenBSD/NetBSD lastcomm(1) flags
NetBSD	`-w`	NetBSD `-w` prints output in as many columns as needed instead of limiting it to 80. Solnix has no `-w`. Source: NetBSD lastcomm(1) -w; Solnix lastcomm(1) SYNOPSIS
FreeBSD, OpenBSD, NetBSD	special terminal names	Solnix documents `--` as terminal-name for no controlling TTY (probably run at boot) and `??` for an undecodable TTY. The BSD pages do not describe these. Source: Solnix lastcomm(1) DESCRIPTION (terminal-name); FreeBSD/OpenBSD/NetBSD lastcomm(1) DESCRIPTION
FreeBSD	default file	FreeBSD documents `/var/account/acct` as the default file. The Solnix page names no default file; it reads the current extended or standard accounting file. OpenBSD and NetBSD say only 'default accounting file'. Source: FreeBSD lastcomm(1) -f; Solnix lastcomm(1) DESCRIPTION; OpenBSD/NetBSD lastcomm(1) -f

Standards

POSIX: lastcomm is not a POSIX.1-2024 utility.

Writing portable scripts

Use only lastcomm [-f file] with optional command, user and terminal operands in portable scripts; it is the only option all four systems document.
Do not parse columns or flag letters across systems: field order, time fields and the meaning of S differ.

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.