What is it?
The initial surge of Linux in the server market has settled down in recent years. But in embedded applications, particularly mobile devices, the open source operating system is soaring.
Global connectivity analysts ABI Research forecast that by 2013, Linux will take 23% of the smartphone market and will be the second most prevalent solution behind Symbian. According to ABI, "Linux solutions will be far more cost-effective than incumbent solutions, even when silicon requirements are taken into account, given that a fuller application layer will be included in the standard package and that the burden of customisation falls mostly on the independent software vendor."
ABI also says Linux solutions will be an important building block in enabling an application domain that embraces Web-based applications and blended Web/native applications.
Motorola, NEC and others are backing Linux and Java on the smartphone. Nokia, which dominates the Symbian Foundation, is downplaying Linux, but recently took over Trolltech, whose best-known products are the industry-leading Linux application development framework, Qt, and Qtopia, an application platform for consumer electronics and mobile devices running embedded Linux.
Then there's OpenMoko, an initiative to develop not only a Linux-based open source mobile phone operating system, but also the open source hardware to run it on. The first OpenMoko phone, the prototype Neo 1973 - now in production as the FreeRunner - comes with a software developer's kit and a screwdriver. OpenMoko has released its CAD files under the Creative Commons license for developers and engineers to use.
Where did it originate?
Motorola launched the first Linux mobile phone in 2003, running MontaVista Hard Hat, the first industrial strength real-time operating system implementation of Linux.
What is it for?
Embedded Linux is stripped down to the essentials needed for security, memory management, process management, network stack and drivers, with additional power management, fast start-up and real-time performance, and other modifications needed for a responsive but resource-limited device.
What makes it special?
Embedded Linux's advantages include not only its low cost and unrestricted distribution, but also its modularity, and the small size of the kernel, combined with free software utilities and lightweight versions of libraries.
How difficult is it to master?
It's probably easier for embedded developers to learn Linux than Linux developers to gain the disciplines of working with constrained resources, where the bugs and downtime typical of desktop software are unacceptable.
Where is it used?
A plethora of products and of competing (and overlapping) alliances has led to fragmentation of effort. But the work seems to be consolidating at last around a few dominant initiatives. The Linux Phone Standards Forum (LIPS) has just announced that it is to "fold in" its activities and membership with the LiMo Foundation. Founded by Motorola, NEC, NTT Docomo, Orange, Panasonic, Samsung and Vodafone, LiMo now has Ericsson, Verizon, MontaVista and Trolltech among its members.
What is coming up?
In September MontaVista is holding a live "webinar" demonstrating its DevRocket IDE in Embedded Linux development.
Rates of pay
C/C++ developers with Embedded Linux £30-45K.