Hello demonstrates the very archetypal first program, used to display a message of the “Hello, World” sort.

It serves as a useful introduction, demonstrating how the simplest of userspace programs can be compiled to run within IMP OS. It references the IMP OS Standard Library for two reasons:

  1. To enable the ability to perform an SWI call, required so that it may call the kernel OS_SetColour functionality and – at the very end – quit itself by calling OS_ProcessExit.
  2. To enable it to call the Standard Library sprintf function, which prints a string of characters on-screen.

It is advisable to check out the repository and view the source which consists of just the one source file: main.c.