Version Matrix¶

This page is the canonical answer to "which Amix version is which". Amix shipped as a short series of releases between 1988 and 1992, and the development line effectively ends at one community patch on top of the last retail release. Two version strings that circulate online — "2.2" and "2.1c, 1994" — are not real and are flagged 🔴 below so you do not trust them.

The single number that matters in practice today: the last retail release is 2.1 ✅ (February 1992 — the month is community-reported 🟡; sources confirm only the year), and the de-facto "final" state of the system is 2.1 patch 2a, whose patched kernel reports itself as 2.1c ✅. Almost everything written for modern emulation and the modern driver repos targets exactly this 2.1p2a / kernel 2.1c combination.

The matrix¶

Version	Date	Lineage / what it is	Notes	Tag
SVR3.x precursors	1988–89	AT&T System V Release 3	A2500UX demos; CPU stepped 68020 → 68030; proprietary windowing (pre-X)	🟡
1.1	1991	SVR4	First widely-referenced SVR4 release; mono X reported "slow as molasses"	🟡
2.0 / 2.01 / 2.03	1991	SVR4	Color X via the A2410 graphics card; archive.org carries the 2.01 and 2.03 installers	🟡
2.1	Feb 1992 🟡	SVR4	Last retail release. Ships pre-formatted man pages only — the `nroff` man sources were dropped	✅ (installer exists locally; month 🟡)
2.1 patch 2a → kernel 2.1c	post-1992	SVR4 patch on 2.1	Unofficial but treated as definitive; inet/NFS/Y2K fixes. Our `patch.adf` is this patch	✅ (the patch ADF exists locally)
"2.2"	—	—	Does not exist in any primary source; almost certainly confusion with 2.1c	🔴
"2.1c, 1994" (gunkies)	—	—	The 1994 date is almost certainly wrong — support ended in 1993	🔴

The Ditto driver paper predates the 2.x line: its page headers read "1990 European Amiga Developer's Conference" ✅. Where it differs from 2.1 (notably the kernel-image name, below) it is documenting an earlier build.

SVR4 vs the SVR3 precursors ✅/🟡¶

Amix as people mean it today is the SVR4 line (1.1 and the 2.x releases). The 1988–89 machines — demoed as the A2500UX, first shown publicly at Uniforum, Dallas, January 1988 🟡 (amigaunix.com places the demo at "the 1988 Uniforum Conference in Dallas" but does not pin the machine or month — those are community-reported) — ran AT&T System V Release 3 with a proprietary windowing system, not X11. ✅ Treat "SVR3 Amix" and "SVR4 Amix" as two different products that share a name. The whole SVR4 codebase was a direct port of AT&T's 3B2 (WE32x00) SVR4 source 🟡 (community-reported; amigaunix.com hedges "it appears that"), which is why so much of the system behaves like a generic 3B2-lineage SVR4 box rather than anything Amiga-specific. See what Amix is for the lineage in full.

2.1 — the last retail release ✅¶

Amix 2.1 is the last release Commodore sold ✅ — February 1992, though the month is community-reported 🟡. It is the version every current guide assumes, because its install media (boot / root / patch floppies) are the set that survived and gets emulated. One concrete, frequently-tripped-over change in 2.1: the distribution carries pre-formatted man pages only — the nroff/troff man sources were removed to save space ✅, so you cannot regenerate or easily edit the manuals on a stock 2.1 system.

Our local boot/root/patch floppies are the 2.1 install set (amix_21_boot.adf, amix_21_root.adf, amix_21_patch.adf). They are proprietary Commodore material — do not redistribute them; obtain them from amigaunix.com or archive.org. Verify any copy against the SHA-256 values in sources/CHECKSUMS.txt and inspect with tools/inspect-adf.sh <image>.

2.1 patch 2a and kernel "2.1c" ✅¶

The practical end of the Amix line is the 2.1 patch 2a release, applied on top of retail 2.1. ✅ After it is applied, the patched kernel identifies itself as 2.1c — this is the same thing, named from the kernel's point of view rather than the patch's. It bundles inet, NFS, and Y2K fixes and is widely regarded as the definitive state of the system.

Our patch.adf is this patch. It self-identifies as:

"Patch Disks 1 and 2 for International, USA-Only, 2-user, and Unlimited-User Amiga UNIX System V Release 4.0 Version 2.1." ✅

Before applying anything, the patch's header script greps the live uname -v and requires it to match:

^2\.1.* 08004..$

So the patch will only install on a genuine 2.1 system ✅ — it refuses unknown versions ("USE AT YOUR OWN RISK") and requires uid=0(root). The mechanics of that self-extracting floppy (the 1 KB bootstrap script, the 070701 cpio archive, the bundled lha and apply) are documented in detail on the patch floppy anatomy page.

Why the version check matters for this matrix: the ^2\.1 pattern is positive evidence that the patched system still reports a 2.1-prefixed version string — consistent with "2.1c" being a 2.1 sub-revision, and with there being no separate 2.2 to match against. ✅

Versions that do not exist 🔴¶

Two strings show up in secondary sources and search results. Neither is real; both are 🔴.

"Amix 2.2" — 🔴 There is no 2.2 in any primary source (no installer, no manual, no uname output). It is most likely a misremembering of 2.1c. Do not cite a 2.2.
"Amix 2.1c, 1994" (as listed on gunkies) — 🔴 The version 2.1c is real (it's the patch-2a kernel, above), but the 1994 date is almost certainly wrong: Commodore's Amix support ended in 1993, and Commodore itself went bankrupt in April 1994 ✅. Treat the 1994 attribution as erroneous; 2.1c is a post-1992 community patch, not a 1994 product.

When you encounter either string in the wild, map it back to 2.1 / 2.1 patch 2a (kernel 2.1c) and move on.

Kernel-image name: `rdbunix` → `relocunix` 🟡¶

A naming detail that trips up anyone cross-reading the 1990 paper against modern repos: the bootable kernel image was renamed across versions 🟡.

Era / source	Kernel-image name	Where it appears
1990 Ditto paper	`rdbunix`	"Adding a device driver" build step
2.1 / modern repos	`relocunix`	`make bootpart KERNEL=relocunix`; the four driver repos

On a modern 2.1 system the build/install step is, for example:

make install                      # produces relocunix
cp relocunix /stand
make bootpart KERNEL=relocunix    # writes the boot partition

This is 🟡 a historical rename — same role (the relinked, boot-partition kernel image), different filename — and it should be verified per version if you ever work with pre-2.1 media. The running kernel itself is /unix; rdbunix/relocunix is the image written to the boot partition. See the boot process and kernel build pages for how that image is produced and installed.

How to read your own system's version¶

On a running system, the authoritative version string is whatever uname reports:

uname -v      # version string the patch greps, e.g. matches ^2\.1.* 08004..$
uname -a      # full string incl. m68k-cbm-sysv4 platform

The platform string is m68k-cbm-sysv4 ✅. If uname -v shows a 2.1-prefixed string ending in an 08004.. build number, you are on retail 2.1 or its 2.1c patch level — that is the only version family you are realistically going to meet today.

Sources¶

Research brief §1 (Identity / lineage / history, including the version matrix) and §13 (open questions / conflicts), sources/research-brief.md.
amix_21_patch.adf analysis via tools/inspect-adf.sh — the patch's self-identification string and the ^2\.1.* 08004..$ uname -v guard (brief §1, §10).
Ditto, Writing Amix Device Drivers, 1990 European Amiga Developer's Conference (the local PDF) — rdbunix kernel-image name and the "Adding a device driver" build step.
The modern driver repos for the relocunix name and make bootpart KERNEL=relocunix: asokero/va2000-amix, isoriano1968/hydra-amix.
Install media and historical/version pages: amigaunix.com; installers on archive.org.
The disputed "2.1c, 1994" listing originates from the Gunkies wiki; the "2.2" string has no primary source (brief §1, §13).