July 2021 - Oberon - mailman3.inf.ethz.ch

Files.Write and 2-byte CHARs
by Arthur Yefimov 21 Jul '21

21 Jul '21

In some Oberon versions, type CHAR has a size of 2 or 4 bytes. (i. e. BlackBox has a 2-byte CHAR, Active Oberon has 4-byte CHAR.) In the latest Oberon language report (2016), the size of type CHAR is not defined, instead CHAR is said to hold "the characters of a standard character set". A new type BYTE is added that is said to hold "the integers between 0 and 255". Now BYTE is used instead of CHAR where it is necessary to work with binary data (or files). Thus, in Project Oberon, module Files now has the following procedures: PROCEDURE ReadByte*(VAR r: Rider; VAR x: BYTE); PROCEDURE ReadBytes*(VAR r: Rider; VAR x: ARRAY OF BYTE; n: INTEGER); PROCEDURE Read*(VAR r: Rider; VAR ch: CHAR); PROCEDURE ReadString*(VAR R: Rider; VAR x: ARRAY OF CHAR); PROCEDURE WriteByte*(VAR r: Rider; x: BYTE); PROCEDURE WriteBytes*(VAR r: Rider; x: ARRAY OF BYTE; n: INTEGER); PROCEDURE Write*(VAR r: Rider; ch: CHAR); PROCEDURE WriteString*(VAR R: Rider; x: ARRAY OF CHAR); The procedure Write is internally the same as WriteByte, and likewise procedure Read is the same as ReadByte, but with different signatures. The only difference is i.e. that r.buf.data[r.bpos] := ORD(ch) is used in Write instead of r.buf.data[r.bpos] := x (as in WriteByte). In Project Oberon, the size of CHAR is 1 byte. But, if CHAR were 2 bytes, module Files should provide a way to read and write the characters in the way that is convenient for the further usage of the file. If CHARs are to be written in a file raw, as a 2-byte integer, then the file would have an encoding of UTF-16, UCS-2 or similar (without BOM), and thus probably it will not display properly in any modern text viewer. My proposal (in case of 2-byte or 4-byte CHARs) is to make Files.Read and Files.Write work with CHARs in the following manner: 1. The file is assumed to be UTF-8 encoded. 2. Files.Read gets one or more bytes from a file and constructs a value of CHAR. 3. Files.Write converts the given CHAR in UTF-8 and puts one or more bytes in a file. The number of bytes read or written for a 2-byte CHAR can be 1, 2 or 3, as UTF-8 takes some bits for itself. For your information: 2-byte version of Unicode covers all modern languages of the world, including Chinese, Japanese, Korean and Thai. The rest 2 bytes of Unicode are used to encode ancient writings, emoji, and some strange things like playing card icons, tiles of the game Mah Jongg, and even dominoes. Additionally, two procedures WriteChar and ReadChar can be added, that write the values of CHARs directly (for fast local non-portable data storage). Kind regards, Arthur Yefimov https://free.oberon.org/en

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Correction: Re: Erratic Mouse Behaviour in A2
by peter＠easthope.ca 21 Jul '21

21 Jul '21

From: peter(a)easthope.ca Date: Wed, 21 Jul 2021 06:32:40 -0700 > ... the pointer ... Original terminology was "cursor" rather than "pointer". ... P.L. -- 48.7693 N, 123.3053 W tel: +1 604 670 0140

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Erratic Mouse Behaviour in A2
by Treutwein Bernhard 21 Jul '21

21 Jul '21

In my Linux32/a2 "installation" my mouse behaves erratically, cursor jumps. Connecting the same mouse to Windows 10 and using Win64/a2 work without problems. Does anybody have an idea? Regards -- Bernhard

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Re: [Oberon] Copy or reinstall A2?
by peter＠easthope.ca 19 Jul '21

19 Jul '21

Liam, From: Liam Proven <lproven(a)gmail.com> Date: Sun, 18 Jul 2021 15:14:05 +0200 > Does anyone know of a way to copy an A2 disk partition from one > machine to another? Or failing that, has anyone any installation tips > for me? If no answer here, try the A2 General Discussion forum. http://cas.inf.ethz.ch/projects/a2/boards Regards, ... P.L. -- 48.7693 N, 123.3053 W tel: +1 604 670 0140

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Re: [Oberon] Copy or reinstall A2?
by peter＠easthope.ca 18 Jul '21

18 Jul '21

Liam, From: Liam Proven <lproven(a)gmail.com> Date: Sun, 18 Jul 2021 15:14:05 +0200 > I can't get any CD image to boot on my Thinkpad W500. In the past, an A2 running on another system could be used to build a bootable installer image. Roughly five years ago an image was built successfully in LinuxA2. That was used to install A2 on a bare 32 bit desktop. The resulting A2 worked and the method should still work. At worst there will be some low level troubleshooting. The method is more powerful now. Create a local working copy of the SVN repository. That will contain executables for ARM, Linux and Windows. Further details here. https://en.wikibooks.org/wiki/Oberon/A2#The_A2_Repository Will be interesting to know the outcome. Regards, ... P.L. -- 48.7693 N, 123.3053 W tel: +1 604 670 0140

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Copy or reinstall A2?
by Liam Proven 18 Jul '21

18 Jul '21

I have been trying to get an OS/2 laptop up and running recently, but I have totally failed. I can't get any CD image to boot on my Thinkpad W500. On my previous try, it did boot OK on my old Thinkpad X200, but I could not sort out disk partitioning... so I made that machine into my A2 and Haiku test machine. So I am now wondering whether to try to move my existing A2 & Haiku installations from the old machine to the new, or reinstall them. Haiku was easy, but installing A2 was excruciating, which is why I don't really want to do it again. I could not get an image on USB to boot, and the machine has no optical drive to use. In the end, I created a VirtualBox VM but pointed it at a real physical disk partition and installed it that way, which worked a treat. Does anyone know of a way to copy an A2 disk partition from one machine to another? Or failing that, has anyone any installation tips for me? At least the W500 does have a working DVD drive, so I could use actual physical media... -- Liam Proven – Profile: https://about.me/liamproven Email: lproven(a)cix.co.uk – gMail/gTalk/gHangouts: lproven(a)gmail.com Twitter/Facebook/LinkedIn/Flickr: lproven – Skype: liamproven UK: +44 7939-087884 – ČR (+ WhatsApp/Telegram/Signal): +420 702 829 053

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Re (2): Writing BootManager using dd.
by peter＠easthope.ca 07 Jul '21

07 Jul '21

From: Treutwein Bernhard <Bernhard.Treutwein(a)Verwaltung.Uni-Muenchen.DE> Date: Tue, 6 Jul 2021 11:08:48 +0000 > be careful, in principle you are correct, but afaik this overwrites > also the partition table (which is located in the last ? bytes of the > boot sector, but I am not really sure about the number of bytes in the > moment). > > As far as I found in the hurry, you need an bs=446 in addition to your > parameters, see > https://homepages.cwi.nl/~aeb/linux/disk/partition_types-2.html#ss2.5 Thanks Bernhard. I'd forgotten that. In fact the MBR is explained in https://en.wikibooks.org/wiki/Oberon/ETH_Oberon/bootmbr salvaged to the wikibook a year or two back. The author could have been Andr Fischer. I don't know. I've added the instructions for dd in section 4.2 of https://en.wikibooks.org/wiki/Oberon/BootManager . With bs=446 for the MBR, the commands succeed. Good opportunity to review and update the documentation. Thx, ... P.L. -- 48.7693 N, 123.3053 W tel: +1 604 670 0140

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Writing BootManager using dd.
by peter＠easthope.ca 06 Jul '21

06 Jul '21

Hi, In ETH Oberon, BootManager can be written to a disk with these commands. Partitions.WriteMBR dev#0 BootManagerMBR.Bin ~ Partitions.FileToPartition dev#0 BootManagerTail.Bin 1 12 ~ I think of this as equivalent in Linux. dd if=~/BootManagerMBR.Bin of=/dev/sdx count=1 dd if=~/BootManagerTail.Bin of=/dev/sdx seek=1 count=12 Corrections? Tips? Thx, ... P.L. -- 48.7693 N, 123.3053 W tel: +1 604 670 0140

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