eCos programs do not have to satisfy any unusual requirements, but there are always some differences between a program written for a real-time operating system as opposed to one written for a time sharing, virtual memory system like UNIX or Windows NT.
This chapter contains checklist of things to remember when writing eCos programs.
The entry point for eCos user programs is usually cyg_user_start() instead of main(), although main() can be used if the ISO C library package is selected. Complete detail on the start-up sequence is given in Chapter 4.