Very similar to a Unix shell like Bash, *Commands are a simple method of providing functionality in RISC OS – it’s especially useful if you’re a programmer, for example, you’d write a !Run or !Boot Obey script that essentially runs through these *commands in order and tells the computer to do something, like start the service or to load a particular configuration file.

*Commands can be entered in RISC OS by clicking the menu button on the RISC OS (or Raspberry Pi) cog in the bottom right of your screen and selecting the Task Window. Alternatively, you can access it by pressing F12 on the desktop, this will open up a command line interface on the bottom of the screen. Pressing enter twice will exit the interface.

When a *Command is used, RISC OS passes the text to OS_CLI. This determines which routine(s) should be called to perform the required action. Using these commands on RISC OS differs from a lot of other operating systems because RISC OS is modular in the way it’s designed – as a result, this means *commands can be altered, added and replaced.

There are commands that can perform a broad range of tasks such as file manipulation, updating date and time, using sound and graphics, networking and system configuration.

The primary way *commands are used on RISC OS are the following:

  • From within Programming Languages, such as BASIC, C/C++, or Assembler
  • Typed via the Command Line Interpreter (CLI)
  • From within applications

Useful resources

RISC OS Open have a comprehensive list of *commands on their website, they also have a very good introduction to *commands which is well worth checking out.

There’s also a list of useful commands on the RISCOSLtd. website, which is quite handy.