"Unlike Embedix, which has a strong (and successful)
emphasis on user friendliness, Hard Hat Linux can be expected to
appeal to current Linux users requiring features specific to
embedded systems. Its configuration and development model follows
the GNU model closely. GCC, GDB, and DDD are used for program
compilation and debugging. SysVinit is used for system
initialization.
In general, the Hard Hat environment should seem familiar to
current Linux users. But in its top-level layout, Hard Hat Linux
more closely resembles the structure of traditional real-time
operating systems (RTOSes) than that of Linux. RTOS vendors
generally deliver a core product which consists of the operating
system and a set of development tools. In addition to this, a
"board support package" (BSP) must be purchased, which provides
drivers and configuration information for each supported single
board computer (SBC) platform. Typically, the RTOS vendor will
produce some BSPs for the most commonly used SBCs; vendors of less
well-known SBCs are expected to produce and sell BSPs for their own
boards. Developers of custom hardware can often start with the BSP
that most closely resembles their design and customize it."