jwste@pbhya.PacBell.COM (Jerry W Steffler) (01/09/89)
Is there a version of Minix for the Amiga? Is anyone working on a version for the Amiga? I am a beginning C programmer (self teach) and do not think that I can port it over with any success. This is my first message posting to the Usenet and I'm not quite sure of the path back to me for any replies. I think part of it is ames!pacbell!pbhya jwste.
ast@cs.vu.nl (Andy Tanenbaum) (01/09/89)
In article <22766@pbhya.PacBell.COM> jwste@pbhya.PacBell.COM (Jerry W Steffler) writes: >Is there a version of Minix for the Amiga? Is anyone working on a version >for the Amiga? I am a beginning C programmer (self teach) and do not think >that I can port it over with any success. I agree. When learning to program, porting a multiprogramming operating system to a piece of poorly documented hardware probably shouldn't be project number 1. Actually, two of my students have started to work on an Amiga port. It is term break now, so I haven't seen them in a while and I don't know how far they are. Andy Tanenbaum (ast@cs.vu.nl)
janhen@wn2.sci.kun.nl (Jan Hendrikx) (01/10/89)
In article <1877@ast.cs.vu.nl>, ast@cs.vu.nl (Andy Tanenbaum) writes: > In article <22766@pbhya.PacBell.COM> jwste@pbhya.PacBell.COM (Jerry W Steffler) writes: > >Is there a version of Minix for the Amiga? Is anyone working on a version > >for the Amiga? I am a beginning C programmer (self teach) and do not think > >that I can port it over with any success. > > I agree. When learning to program, porting a multiprogramming operating > system to a piece of poorly documented hardware probably shouldn't be project > number 1. > Andy Tanenbaum (ast@cs.vu.nl) I wouldn't call the Amiga 'poorly documented hardware'. There is something called '(Commodore-Amiga) Hardware Reference Manual', published by Addison/Wesley, that contains (almost) all information you normally should not want to know. And besides, the Amiga already has a proper multitasking operating system. -Olaf Seibert
vandys@hpcupt1.HP.COM (Andrew Valencia(Seattle)) (01/12/89)
/ hpcupt1:comp.os.minix / janhen@wn2.sci.kun.nl (Jan Hendrikx) / 5:30 am Jan 10, 1989 / > ...And besides, the Amiga already >has a proper multitasking operating system. SOURCE man! Give me SOURCE! Andy
HELMER%SDNET.BITNET@vm1.nodak.edu (Guy Helmer) (01/12/89)
In a recent posting, Olaf Seibert writes: >In article <1877@ast.cs.vu.nl>, ast@cs.vu.nl (Andy Tanenbaum) writes: >> In article <22766@pbhya.PacBell.COM> jwste@pbhya.PacBell.COM (Jerry W > Steffler) writes: >> >(irrelevant stuff deleted...) >> >> I agree. When learning to program, porting a multiprogramming operating >>system to a piece of poorly documented hardware probably shouldn't be project >> number 1. >> Andy Tanenbaum (ast@cs.vu.nl) > >I wouldn't call the Amiga 'poorly documented hardware'. There is >something called '(Commodore-Amiga) Hardware Reference Manual', >published by Addison/Wesley, that contains (almost) all information >you normally should not want to know. And besides, the Amiga already >has a proper multitasking operating system. The documentation you refer to is hardly understandable and mostly unusable, besides being inconsistent and incomplete. As for having a proper multitasking operating system, the Amiga is in desperate need of an operating system that doesn't just crash every so often for fun. I tried to write programs on the Amiga using AmigaDOS, and I quickly went back to using my stable (but single-tasking) PC-DOS on my 8088 machine. - Guy Helmer, South Dakota School of Mines and Technology
janhen@wn2.sci.kun.nl (Jan Hendrikx) (01/13/89)
In article <6537@louie.udel.EDU>, HELMER%SDNET.BITNET@vm1.nodak.edu (Guy Helmer) writes: > (irrelevant stuff deleted...) > In a recent posting, Olaf Seibert writes: > >I wouldn't call the Amiga 'poorly documented hardware'. There is > >something called '(Commodore-Amiga) Hardware Reference Manual', > >published by Addison/Wesley, that contains (almost) all information > >you normally should not want to know. And besides, the Amiga already > >has a proper multitasking operating system. > > The documentation you refer to is hardly understandable and mostly unusable, > besides being inconsistent and incomplete. Did you really read the hardware manual? I do have it, and most of it is perfectly understandable and complete. Even for me, while I am just a software type. The only part where it gets inconsistent is when discussing the exact timing of the video DMA. But that is easily cleared up when you look at the nice illustration of cycle useage. And of course, almost everything in that manual is unusable, since in a multitasking system the only one to go straight to the hardware is the operating system itself (as you should know from Minix). > As for having a proper > multitasking operating system, the Amiga is in desperate need of an > operating system that doesn't just crash every so often for fun. I > tried to write programs on the Amiga using AmigaDOS, and I quickly > went back to using my stable (but single-tasking) PC-DOS on my 8088 > machine. Did you ever write a device driver for minix during an operating systems course? I did, and I can assure you that it always crashes for the same reason that an Amiga also crashes: programming errors. Minix does not crash for fun; neither does the Amiga O/S. And writing a new device driver for the Amiga is lots easier than for any unix variant. > - Guy Helmer, South Dakota School of Mines and Technology -Olaf Seibert.
ugkamins@sunybcs.uucp (John Kaminski) (01/14/89)
In article <299@wn2.sci.kun.nl> janhen@wn2.sci.kun.nl (Jan Hendrikx) writes: >In article <1877@ast.cs.vu.nl>, ast@cs.vu.nl (Andy Tanenbaum) writes: >> In article <22766@pbhya.PacBell.COM> jwste@pbhya.PacBell.COM (Jerry W Steffler) writes: [ ... material deleted ... ] > >I wouldn't call the Amiga 'poorly documented hardware'. There is >something called '(Commodore-Amiga) Hardware Reference Manual', >published by Addison/Wesley, that contains (almost) all information >you normally should not want to know. And besides, the Amiga already >has a proper multitasking operating system. > >-Olaf Seibert I agree that C-A has the Hardware Ref. and that *should* point out all the necessary details to get any OS ported. I have not had the fortune of laying my eyes upon this doc, but if it is anything like the manuals I *DO* have, it may be quite cryptic or incomplete in its presentation. For instance, after reading over the (fairly thick) Libraries and Devices doc, the serial.device docs are the only ones (that I remember anyway) that mention that the I/O request block is returned not only by the I/O call itself (by referencing through the pointer it is handed and depositing the results there) but also to the message port mentioned in the I/O request block. I'm not entirely sure, but I'm pretty sure all the device handlers do that, but the serial.device is the only one that mentions it explicitly (again, the only one that I recall that mentions it). I also agree that the Amiga has a multitasking operating system. What con- stitutes "proper" is all relative. If you are looking for just anything to run the machine, fine. If you would like to be UNIX (tm) compatible, you must opt for something else. I wonder if you have program- med with Lattice C at all. The lc.lib has all sorts of UNIX-like calls, but, of course, they are not true UNIX. For example, there is an open() call, but you must hand it a legal AmigaDOS filename. A UNIX filename like "../userdata/mydat.txt" simply won't do. Also, UNIX is superior in many ways, the least of which is that any program may be asynchronously aborted or at least signalled that an abort is desired, compared to just setting one of the signal bits in the Amiga task control structure (it must always be polled). I imagine the only major thing you would lose (at least until someone hacks a solution) is the nice window and screen system (For the non-Amiga-ites on the net, Amiga's graphic interface, Intuition, maintains virtual screens of any hardware-legal composition (resolution, colors, etc.) that can be "dragged" up or down, being rendered in layers. This means if you have a screen with twice the vertical resolution (interlaced mode) pulled down half way on the workbench (default) screen, you will see half a monitor of regular screen and half a monitor of interlaced screen. This is really nice in many circumstances).
janhen@wn2.sci.kun.nl (Jan Hendrikx) (01/15/89)
In article <3663@cs.Buffalo.EDU>, ugkamins@sunybcs.uucp (John Kaminski) writes: |In article <299@wn2.sci.kun.nl> janhen@wn2.sci.kun.nl (Olaf Seibert) writes: |[ ... material deleted ... ] |> |>I wouldn't call the Amiga 'poorly documented hardware'. There is |>something called '(Commodore-Amiga) Hardware Reference Manual', |>published by Addison/Wesley, that contains (almost) all information |>you normally should not want to know. And besides, the Amiga already |>has a proper multitasking operating system. |> |>-Olaf Seibert | |I agree that C-A has the Hardware Ref. and that *should* point out all the |necessary details to get any OS ported. I have not had the fortune of laying |my eyes upon this doc, but if it is anything like the manuals I *DO* have, |it may be quite cryptic or incomplete in its presentation. For instance, [example about doing Exec IO with various devices] The principles of Exec IO are explained in the Exec manual, so the things that remain the same across all devices are not repeated all over the place. |I also agree that the Amiga has a multitasking operating system. What con- |stitutes "proper" is all relative. [explanation of a number of differences between unix and AmigaOS] If I paraphrase your words this way, I must agree that AmigaOS is not Unix, and of course it isn't. Each has its own good and bad points. -Olaf Seibert
jesup@cbmvax.UUCP (Randell Jesup) (01/17/89)
In article <3663@cs.Buffalo.EDU> ugkamins@sunybcs.UUCP (John Kaminski) writes: >In article <299@wn2.sci.kun.nl> janhen@wn2.sci.kun.nl (Jan Hendrikx) writes: >>I wouldn't call the Amiga 'poorly documented hardware'. There is >>something called '(Commodore-Amiga) Hardware Reference Manual', >>published by Addison/Wesley, that contains (almost) all information >>you normally should not want to know. And besides, the Amiga already >>has a proper multitasking operating system. >> >>-Olaf Seibert > >I agree that C-A has the Hardware Ref. and that *should* point out all the >necessary details to get any OS ported. I have not had the fortune of laying >my eyes upon this doc, but if it is anything like the manuals I *DO* have, >it may be quite cryptic or incomplete in its presentation. For instance, >after reading over the (fairly thick) Libraries and Devices doc, the >serial.device docs are the only ones (that I remember anyway) that mention >that the I/O request block is returned not only by the I/O call itself >(by referencing through the pointer it is handed and depositing the results >there) but also to the message port mentioned in the I/O request block. >I'm not entirely sure, but I'm pretty sure all the device handlers do that, >but the serial.device is the only one that mentions it explicitly (again, the >only one that I recall that mentions it). The hardware manual has everything you need to know about the hardware. The discussion of devices assumes you've read the Exec section on how IO devices on the amiga work, the individual chapters on each device mainly outline the differences, and give examples. >I also agree that the Amiga has a multitasking operating system. What con- >stitutes "proper" is all relative. If you are looking for just >anything to run the machine, fine. If you would like to be UNIX (tm) >compatible, you must opt for something else. I wonder if you have program- >med with Lattice C at all. The lc.lib has all sorts of UNIX-like calls, >but, of course, they are not true UNIX. For example, there is an open() >call, but you must hand it a legal AmigaDOS filename. A UNIX filename like >"../userdata/mydat.txt" simply won't do. So? It's not unix, and doesn't pretend to be. We offer Sys V.3 Unix for the Amiga (requires A2620 68020 board with MMU). The Amiga OS is, however, realtime; it can do a number of things better/faster than unix can. This is required to get reasonable performance on a 68000, and the LWPs (light weight processes) make writing multi-tasking programs much more feasible. In return, it is more vunerable than a protected unix to poorly written programs (and in the early releases (1985), the OS - certainly no longer true). This is more a factor of no MMU than OS design, though. What happens with ST Minix is a program goes off with a stray pointer? Sure, Lattice C has a Unix-like library. So does every ANSI-compliant compiler I know of. Very very few that don't run on unix would handle unix file names. If you make assumptions about where things live on unix, such things will break on different Unixes as well. > Also, UNIX is superior in many ways, >the least of which is that any program may be asynchronously aborted or at >least signalled that an abort is desired, compared to just setting one of the >signal bits in the Amiga task control structure (it must always be polled). An amiga program must release it's own resources. This is because full resource tracking was considered too expensive, and a headache when resources may be passed from task to task. You don't have to poll signal bits, you can have them cause exceptions to execute (ala signal handlers in unix). Caveat is that exception handlers can't modify the process state too much, or call many OS functions, since the main process may be in the middle of an OS call, and have resources locked. >I imagine the only major thing you would lose (at least until someone hacks >a solution) is the nice window and screen system (For the non-Amiga-ites on >the net, Amiga's graphic interface, Intuition, maintains virtual screens of >any hardware-legal composition (resolution, colors, etc.) that can be >"dragged" up or down, being rendered in layers. This means if you have a >screen with twice the vertical resolution (interlaced mode) pulled down >half way on the workbench (default) screen, you will see half a monitor of >regular screen and half a monitor of interlaced screen. This is really nice >in many circumstances). Screens (virtual displays that can be depth arranged and dragged) are a wonderous concept, and make a windowing system much nicer (and less cluttered). You'd also lose all use of 3rd party hardware (though you MIGHT be able to hack up an equivalent to the expansion.library, that configures expansion boards, to get ram into the system.) 3rd party drivers would break, so no HD, no serial ports, etc. You'd be in the same position as our Unix port team: having to write everything from scratch (I think they should have made the unix kernal run under (a slightly modified) version of exec, etc. But that was their groups decision. It does reduce interactions.) -- Randell Jesup, Commodore Engineering {uunet|rutgers|allegra}!cbmvax!jesup