OSDev.org

I was wandering, Is there anything except for APIs, syscalls, memory management (and possibly device management in certain cases) and executable format that make an executable os specific?
Thanks in advance,

Jules

Endian-ness and architecture? There isn't much left, really. At the simplest level all code looks the same. It's the dependencies and the wrapping that makes code OS specific.

Well, for a singlethreaded singletasking app, they all look the same at their cores. However, an OS can (and usually will) provide computational abstractions as well as hardware abstractions, for userapps. If an app is built to use computational abstractions from a particular OS -- then that will also define an excluded set of OSes that cannot support the app. Will an app that is designed to run on Singularity run on most other OSes? I doubt it. The other OSes will not be abstracted in the right ways to even support the computational methods. Perhaps Singularity is a bad example (I'm not very familiar with it) -- but I think you get my point, anyway.

As long as programs are compiled for the same architecture and endianess, they can theoretically run on any operating system under that architecture as long as their expected API is implemented. This is exactly what programs such as WINE and LINE do. For a simple example, look at one of my old projects at http://xpapi.sf.net