An open source start-up has given the first preview of a project designed to significantly blur the boundaries between Linux and other operating systems, by allowing Linux programs to run on Windows and Mac OS X.

The project, called Lina, was given its first showing at the Open Source Business Conference in San Francisco last week and is due to be released late in June under both the GPL and a commercial licence.

Developers compared it to Java, with its write-once, run-anywhere ethos, but unlike Java, Lina is intended for full-scale applications, with support for languages such as C/C++, Perl and Python.

It takes the form of an application written for the host system, which virtualises the underlying x86 hardware. This runs a modified Linux kernel, currently version 2.6.19, along with a standard Linux file system and libraries, mapped to the equivalent resources on the host platform.

The package is currently a 15MB download, expanding to 40MB.

The software includes resources allowing Linux applications to match the look and feel of the host operating system, Windows or Mac OS X, something that has been a difficulty in previous cross-platform efforts.

Applications must be compiled for Lina, something the company compared to compiling for any other Linux distribution.

"Developers get the users they want (while) Windows and Mac users get to run an incredible number of open source programs without having to learn a new operating system," said Lina chief executive James McGreen in a statement.

While there are some Linux-specific applications, such as scientific tools, that Windows and Mac users might want access to, part of the company's plan is to make Lina attractive in its own right as a cross-platform development tool.

The argument goes that developers would be able to market to users of all three operating systems with a single executable. By using open source tools developers would also gain access to a large body of existing, reusable open source components.

The programs they create, meanwhile, would become instantly accessible to any Linux user.

The company made it clear that after four years of development Lina is still at an early stage of development, with support currently limited to web applications and command-line tools. The idea behind next month's initial release is to get the open source community interested, and to gather momentum around the project.

"We want the critical feedback of the open source community, particularly in regard to our interfaces and APIs, so we've made it a priority over the past few months to prepare for an open source release," the company said in release notes on its website.