Oberon/ETH Oberon

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Links[edit | edit source]

ETH Oberon Sitemap
ETH Oberon Tutorial
ETH Oberon White Paper
Contributions, formerly served from the ETHZ

Installing[edit | edit source]

The Oberon0 installer for ETH Oberon running under QEMU in Debian Linux.

Originally, Oberon was installed on a bare 32 bit i386 or i486 machine using an Oberon0 diskette. The procedure may still interest an enthusiast.

In a contemporary system the Oberon0 installer can run on a virtual machine. The virtual machine is installed once and can be used for any number of installations. With this method, no time is spent recording and booting from a diskette and the unreliability of diskettes and drives is avoided. The installer runs faster on the virtual machine than it does from a diskette. The method has proven successful in installing ETH Oberon to a variety of laptop and desktop machines including a Micron Trek 2, AGP laptop. Detailed instructions for installation with the QEMU hypervisor are provided and the instructions can be adapted to other virtual machines.

Andres Ramos describes a method where a FAT filesystem on a diskette is used to transfer installation files to the target machine.

System configuration notes in QEMU page are independent of method of installation. In the original installation notes, configuration is discussed under the heading Customization of the installed Native Oberon system. In the running ETH Oberon, Script.Open System.Text allows access to section "4. Configuring the system".

After installation and configuration on a storage medium, the system can run directly on a native X86 PC. Alternatively, use can continue on the virtual machine. In the native case, a network connection will be over Ethernet or a serial crossover cable. In the virtual case, a network connection uses a TAP or bridge interface connected to the host system.

A Calendar and a Clock[edit | edit source]

An Oberon document named Time with the hook caret allowing insertion.
Time with the calendar and clock.

Open an empty Time document with MM on Desktops.OpenDoc Time ~.
Set the hook caret by ML in the document.
Insert a calendar with MM on Gadgets.Insert Clocks.NewCalendar ~.
Insert a clock with MM on Gadgets.Insert Clocks.NewClock ~.
MM on [Store].
MM on [Close].
MM on Edit.Open Oberon.Text ~. Alternatively ET.Open Oberon.Text ~.
Above the line { System.OpenLog } insert these two lines.

{ Desktops.OpenDoc Time ~ }
{ Configuration.Marker set 80% 92% }

MM on Edit.Store or ET.Store.
MM on System.Reboot.

Telnet Console[edit | edit source]

Telnet is an insecure protocol but provides a host console in Oberon and in an Oberon sub-system of A2. A host of an Oberon subsystem and a network facing router in a LAN should have a firewall such as Shorewall.

A telnet server daemon is required on at least one host. This in Linux.

sudo apt install openbsd-inetd inetutils-telnetd

Configure with this line in /etc/inetd.conf.

telnet stream tcp nowait <user> /usr/sbin/tcpd /usr/sbin/telnetd -E bin/bash

Refer to the telnetd manual. <user> must be replaced with the id of the Oberon user. Note the default to no authentication; equivalent to parameter "-a none". Restart the inet daemon.

service openbsd-inetd restart

Try telnet from within a console in the host.

telnet localhost

Then in Oberon.

Desktops.OpenDoc telnet://localhost

To be automatically located in the home directory, append this line to ~/.bashrc.

cd ~

Email[edit | edit source]

Mail.Panel in Oberon.

Oberon supports POP and POP3 for retrieving e-mail and SMTP for sending it. E-mail can be received from a smarthost via Stunnel and sent via Exim with TLS.[1] TLS is routine practice, essential for security.

In Oberon.Text (Oberon.<host>.Text if using myaos in UnixAos or A2) make these settings.

NetSystem = {
  SMTP = "localhost"  {* outgoing exim4 mail server *}
  POP = "localhost"  {* stunnel to incoming mail server *}
  POPMode = "POP3"  {* POP3 or APOP *} 
  EMail = "me@my.domain.name"  {* your return address *}

Ports 25 for SMTP and 110 for POP are visible in Oberon.Mail.Mod.

In contemporary practice, TLS is advisable for the connection to the smarthost. Install stunnel on a host and configure as in this example. The server name and port, exemplified by my.email.server:995, should be adapted to context.

# localhost:/etc/stunnel/stunnel.conf
# Example SSL client mode services 
client = yes 
accept = localhost:110 
connect = my.email.server:995

Set POP authentication using NetSystem.SetUser as in this example.

NetSystem.SetUser pop:myEmailID:myEmailPassword@my.email.server ~

The original SetUser command assumed the @ character did not occur in myEmailID or in myEmailPassword. This command, for example, would fail.

NetSystem.SetUser pop:me@my.domain.name:r2d2$8Ch@my.email.server ~

The difficulty is resolved by more thorough parsing in the SetUser command. Retrieve the revised NetSystem.Mod in ETH Oberon; Unix.Oberon.NetSystem.Mod in A2. Compile the module. In ETH Oberon.

Compiler.Compile NetSystem.Mod ~

In A2 apply the compile button in the editor (menu Files > Files > Unix.Oberon.NetSystem.Mod > MM MM) or MM on this command.

Compiler.Compile Unix.Oberon.NetSystem.Mod ~

Install Exim in the host according to system specific documentation for Debian, Fedora/CentOS and etc.[2] Exim authenticates to a smarthost according to a password file.[3] Details of configuration for a specific mail server can be obscure. For example, the server can fail to specify STARTTLS or TLS on connect. Before attempting to configure Exim, ambiguities are best resolved using Swaks. Replace arguments of Swaks options -au, -ap, -f and -t with appropriate values for user, password and email address. Refer to the excellent manual for details. A userid pattern commonly used by ISPs is me@my.authentication.domain.

swaks -tls \
      -ao -apt -au me@my.authentication.domain -ap r2d2\$8Ch \
      -s my.smarthost.com --port 587 \
      -f me@my.email.address -t me@my.email.address

The example password has eight characters; \ is not included in the password but prevents misinterpretation of $8 by the host shell.[4] Swaks creates a trivial test message automatically. Arguments of options can be adjusted until transmission succeeds. Confirm transmission by receipt in Oberon as discussed above.

News Reader[edit | edit source]

Notes pending.

Text[edit | edit source]

These tables show the structure of records in memory representing a Text. When Texts.Store() records a Text in a file for a storage medium, the information in the record structure is serialized. In the inverse process, Texts.Load() deserializes the information to the record structure of the Text in memory.

TextDesc is an extension of Objects.ObjDesc. The fields added to make TextDesc are distinguished from the fields inherited from ObjDesc by a differing background color.

The Type Text
Type Fields of
Types of Fields Notes
Texts.Text, a pointer to a Texts.TextDesc stamp LONGINT Integer
dlink Objects.Object Pointer
slink Objects.Object Pointer
lib Objects.Library Pointer
handle Objects.Handler Pointer
len LONGINT Length of text.
obs Objects.Library Pointer
trailer Texts.Piece Pointer to Sentinel node in list of pieces.
org LONGINT Offset in [0,len) of first character in last found piece.
pce Texts.Piece Last found piece.
Objects.Library in the table above
Type Fields of LibDesc Types of Fields Notes
Objects.Library, a pointer to a LibDesc next Objects.Library Pointer
ind Objects.Index Pointer
f Files.File Pointer
R Files.Rider Pointer
name Objects.Name  
dict Objects.Dictionary Pointer
maxref INTEGER  
Type Fields of PieceDesc Types of Fields Notes
Texts.Piece, a pointer to a Texts.PieceDesc f Files.File Pointer
off LONGINT Integer
obj Objects.Object Pointer
lib Objects.Library Pointer
prev Piece Pointer
next Piece Pointer

Texts.FindPiece and the cache[edit | edit source]

For a given Text, T, and offset pos in [0, T.len), procedure Texts.FindPiece has the task of locating the piece containing pos. At each execution, FindPiece could begin at offset 0 and add lengths of pieces until the piece containing pos is located. A cache based upon T.pce and T.org allows better efficiency. When FindPiece completes a search, the pointer to the found piece is recorded in T.pce; the offset of the first character of that piece is recorded in T.org. The next execution of FindPiece begins at that cached location. With a result from FindPiece often being near the preceeding result, this strategy avoids repeated summation of lengths from the beginning of the first piece.

Text Dataflow in ETH Oberon[edit | edit source]

This dataflow example illustrates relationships between Oberon Text, HTML and ASCII text.

Oberon Text with
non-text features
Oberon Text with non
-text features omitted
      Oberon Text with non
-text features omitted
MediaWiki markup with color
and syle but hyperlinks
and images omitted
HTML5 text with
text color and style
Clipboard or
Save operation
text file

Text color and style, images and hyperlinks are lost by conversion of browser text to ASCII. Consequently the rightmost Oberon Text has the same appearance as plain ASCII text. Text color and style can assist with reading and understanding a source but compilation is not influenced by color and style.

Module Sources[edit | edit source]

The last release of ETH_Oberon at the ETHZ was 2.3.7. At bootup, release date 2003-01-05[5] is announced in the System.Log. Sourceforge has the file "Native Oberon 2.3.7 Alpha/NativeOberon_2.3.7.tar.gz" and bootable installer images in "Oberon0 boot disk/". Package structure is in Native.Tool. Sources are also available at https://github.com/schierlm/NativeOberon-2.3.6-Extracted in the directory FullInstall_ASCII. Sources and Tools remain under the ETH Oberon License.

Module Sources in System Package[edit | edit source]

The System Package contains approximately 170 modules. Refer to Native.Tool.

Release 2.3.7 Wikibook variant[6] Notes
ATADisks.Mod ATADisks.Mod Support for Compact Flash added.
Dialer.Mod Dialer.Mod Dialer.Dial modified to support the ringback protocol as provided by mgetty. Refer to the Dialer page.
Input.Mod Input.Mod
PPPMain.Mod PPPMain.Mod
PPPTools.Mod PPPTools.Mod

Module Sources in Gadgets Package[edit | edit source]

Release 2.3.7 Wikibook variant[6] Notes
Mail.Mod Mail.Mod

Module Source in Apps1 Package[edit | edit source]

Release 2.3.7 Wikibook variant[6] Notes

Module Sources in Apps2 Package[edit | edit source]

Release 2.3.7 Wikibook variant[6] Notes

Module Sources in Documentation Package[edit | edit source]

Release 2.3.7 Wikibook variant[6] Notes

Module Sources in Build Package[edit | edit source]

Release 2.3.7 Wikibook variant[6] Notes

Module Source in Lab Package[edit | edit source]

Release 2.3.7 Wikibook variant[6] Notes

Source for Additional Module[edit | edit source]

Release 2.3.7 Wikibook variant[6] Notes
MediaWiki.Mod Translation of Oberon Text to MediaWiki markup.

Texts[edit | edit source]

Release 2.3.7 Wikibook variant[6] Notes
Oberon.Text Oberon.Text Edit according to local requirements and preferences.

Tools[edit | edit source]

Release 2.3.7 Wikibook variant[6] Notes

Footnotes[edit | edit source]

  1. The same functionality of the Mail.Panel is available in ETH Oberon when another local host provides Exim and Stunnel.
  2. The primary Exim documentation is also available.
  3. In Debian, /etc/exim4/passwd.client associates a password with each (host, user) pair. Multiple host:user:password specifications are acceptable. The file does not determine the destination chosen by exim for sending a message. Refer to the exim4-config_files manual.
  4. No escape character is involved in Oberon.
  5. ISO 8601 date format.
  6. a b c d e f g h i j Compare ETHZ and wikibook sources using Diff.Do in Oberon or the MediaWiki facility described on the front page.