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!System updates


This page provides system resources, including toolbox and other modules, for RISC OS 3 and RISC OS 4 systems enabling them to use software developed with Castle Technology's new Acorn C/C++ Development Environment. Developers may download and freely distribute these resources.

Users may need to download and install some of these files in order to use some new software, for example because an application complains that a module is missing or out of date.

As a general guideline, we recommend the following:

RISC OS 3.10, 3.50:
Download and install TBox/zip to install of the system resources including the Toolbox modules that may be needed in order to use applications developed with the latest Acorn C/C++ compiler.
RISC OS 3.60 or RISC OS 4:
Download and install System/zip to install the latest Shared C Library (CLib), CallASWI and FPEmulator modules.
The !System update includes version 5.53 of the SharedCLibrary module, which is the version that is in RISC OS 5.03. It is strongly recommended that contact Castle if you still do not have RISC OS 5.03 on your IYONIX pc

If a new piece of software is reporting that it needs a new module, then check the list below and download the file that contains the required module.

If in doubt, you can download and install TBox/zip which includes all of the system modules that Castle Technology have released.

Latest releases

These 26-bit modules are for use on RISC OS 3 and RISC OS 4 computers only - they are NOT needed on the IYONIX pc which has 32-bit versions of these modules built-in.



Latest CallASWI module: Basic !System needed for C programs - recommended for users with RISC OS 3.60 and later: Full !System including all of the files in System/zip plus the following modules - recommended for users with RISC OS 3.10 and 3.50:
  • CallASWI 0.03
  • CallASWI 0.03
  • CLib 5.53 (Shared C Library)
  • FPEmulator 4.19
  • Installer 0.09
  • BorderUtil 0.05
  • DDEUtils 1.53
  • DragAnObj 0.02
  • DragASprit 0.10
  • Drawfile 1.43
  • FilterMgr 0.09 (Filter Manager)
  • FrontEnd 1.28
  • Picker 0.31 (Colour Picker)
  • RedrawMgr 0.06
  • TaskWindow 0.68
  • TinyStubs 0.02
Toolbox modules:
  • ColourDbox 0.17
  • ColourMenu 0.19
  • DCS_Quit 1.08 (DCS Object)
  • FileInfo 0.16
  • FontDbox 0.16
  • FontMenu 0.21
  • IconBar 1.18
  • Menu 0.32
  • PrintDbox 0.14
  • ProgInfo 0.14
  • SaveAs 0.15
  • Scale 0.13
  • ToolAction 0.15
  • Toolbox 1.41
  • Window 1.47

Installing the modules

To install the system modules provided on a RISC OS 3 or RISC OS 4 computer you need SparkPlug, SparkFS or some other way of opening Zip archives.

  1. If you are using SparkFS open the Zip archive and double-click on !SysMerge.
  2. If you are using SparkPlug or another de-archiver open the Zip archive, drag the files to a directory on disc and double-click on the !SysMerge that was copied out of the Zip archive (not the one in the Zip archive).

SysMerge should only take a couple of seconds to run and it will only display a message if it fails for any reason. It works as follows:

  1. For modules it looks at the version number inside each module and installs it if it doesn't already exist in !System or if an older version of the module exists in !System. If the module version number is the same as the module already installed in !System then it installs the new module if it has a later date stamp.
  2. Other files are installed if the date stamp is later than that of the corresponding file in !System, or if it doesn't already exist in !System.

Loading CLib on RISC OS Select

RISC OS Select version 1 would not allow the Shared C library to be soft-loaded. The latest version of RISC OS Select known as RISC OS Select 2i3 or RISC OS 4.33 (Kernel 6.24) has now been released by RISC OS Ltd and removes this restriction.

Frequently asked questions

  What are system resources?
  The system resources provided here are used by many RISC OS applications. They provide updates and extensions to RISC OS that may be required by new software. The required modules are often supplied on disc with each program, ready to be installed in the !System directory, but in some cases you may need to install the modules provided here.
  I have an IYONIX pc do I need these modules?
  No, the IYONIX pc already has 32-bit versions of these modules. Updates will be installed automatically along with Operating System updates.
  Why should I install these modules?
  If an application fails to load and reports that it needs a particular module you should download and install one of the above zip files, depending on which module you need
  My applications all work OK, should I install the modules?
  Running the SysMerge utility will not do any harm - it will upgrade any modules that it can but it will not overwrite any later modules that are already installed with the modules supplied here.
  I can't remember whether I have run !SysMerge already. Can I run it again?
  Yes. !SysMerge only installs new files. If they are already installed it will do nothing.
  What if I need a later module that is not supplied here?
  If an application says it needs a module version later than those listed above you should contact the publisher, although it should normally be provided with the application.
  What if I have some later modules installed already?
  The SysMerge utility only installs these modules if they are later than the ones already installed on your system. It will not install an old module over a new one.
  A new !System directory was supplied with a new piece of software. Which should I install?
  Install the !System that was supplied, as instructed. If you wish you may download and install the System/zip files too to ensure that you have the latest versions. This is quite safe - the SysMerge utility will only install modules if they are newer that the ones already installed.
  Can I use these modules with RISC OS 2 or RISC OS 3.00?
  No, they are only suitable for RISC OS 3.10 and later.
  Can I use these modules with RISC OS Select?

It is recommended that the System/zip files are installed on RISC OS Select. The Toolbox modules are not needed as they are already provided in ROM and in some cases later versions are supplied with RISC OS Select. You should upgrade to Select 2 if you haven't already as Select 1 does not allow the Shared C library (CLib) to be soft-loaded.

  Why is it important that developers test using these modules?
  The modules supplied with the IYONIX pc have similar functionality to those supplied here. If you cannot test your software on an IYONIX pc then you should test it using these modules.
  How do I know which modules are in ROM?
  Press Ctrl-f12 to open a task window and type *ROMmodules
  How do I find a module version number?

Press Ctrl-f12 and type *Help followed by the module name. If the module is loaded you will see the module version number displayed.

If you are curious you can also read a module version number from a module file by holding shift and double clicking on the file. This will load the binary file into a text editor and somewhere in the first few lines you should see a module version number. This is not normally necessary and if you do load a module like this take great care not to modify the file or save it.

  When were the Toolbox modules introduced?
  They were originally supplied with the Acorn C/C++ development environment in 1994 and were included in the RISC OS 3.60 ROMs. Note that the Toolbox modules were not supplied wtih RISC OS 3.50.
  Where do I find the !System directory:
  On RISC OS 3.50 and later the !System directory lives inside !Boot and may be accessed by holding shift and double-clicking first on !Boot and then on !System. On earlier systems it should be on your hard disc (or your system floppy disc if you do not have a hard disc). You shouldn't need to open it to install the new files as !SysMerge will install the files there automatically.
  Where can I find documentation on the CallASWI module?
  See the CallASWI page on this site.

Notes for software developers

The 26-bit modules provided here are suitable for RISC OS 3 (version 3.10 and later) and RISC OS 4. They are not suitable for use on the IYONIX pc which is supplied with later 32-bit versions. Attempting to install them on the IYONIX pc using the supplied SysMerge tool will have no effect.

RISC OS 3.00 and earlier versions are no longer supported.

Where software is distributed via the Internet users should be referred to the page for the latest !System update.

Where software is distributed on disc to users who may not have Internet access it is recommended that the appropriate !System and !SysMerge is distributed at the same time.

Developers distributing Toolbox applications on disc should distribute the contents of TBox/zip with their software if the software is intended for RISC OS 3.10. Any modules that are not needed for the application may be removed but note that you need to edit the !SysMerge file if you remove any files.

Developers may distribute the contents of System/zip instead if RISC OS 3.10 and 3.50 are not being supported, as all users with RISC OS 3.60 and later should already have the other system and toolbox modules installed (note that the Toolbox modules were introduced in the RISC OS 3.60 ROMs - they were not supplied with RISC OS 3.50).

The Shared C Library (CLib) is required by all C programs produced with the latest 32-bit Acorn C/C++ Development Environment (or at least all C programs that are linked against the 32-bit Shared C library). It is important that that CLib 5.45 (or later) is installed so that these programs may be used on RISC OS 3 and RISC OS 4 systems.

CLib 5.45 adds long long maths functions which were missing from earlier versions.

The Toolbox modules supplied here are equivalent to the ones supplied on the IYONIX pc although the version numbers are different. Although it is not essential to use these Toolbox modules with software that has been compiled using the latest C compiler it is essential that all software is tested using these versions before release.

Software that is intended for use with RISC OS 5 should ideally be tested on an IYONIX pc. If you do not have access to one you should at least ensure that your software has been tested using the modules supplied here as they are equivalent to the ones supplied with RISC OS 5. To do this you will need to copy your existing modules to a safe place and manually install these modules - you should not use SysMerge in this case as it will not replace later modules with earlier ones.

Be aware that modules released by RISC OS Ltd may have the same module name and version number as IYONIX modules even though the module is different although we are not aware of this causing any problems at this time.

Applications should RMEnsure the absolute lowest module number that they require. They should not RMEnsure the latest version (even if the module is supplied with the application) unless they really do require it as explained in the section C programs.

© 2006 IYONIX Ltd 32-bit RISC OS