| This paper presents the design and realization of the special file system, which is for embedded GIS application software applied in military tactics wireless information terminal. We first put forward the file system of hierarchy structure through an object-oriented programming approach. To deal with great amount of data from geographic information and the need of fast access, we design a kind of professional embedded GIS data structure to combine the quad tree storage format and the deploying mode of the file system. This method can implement the fast access for geographic information data. The basic functions of file system and functions of fast accessing GIS space information are available in our designed file system. This file system accords with the standard ANSI C data structure and code design, so it can be replanted to other operation systems to meet the demand of terminal application software. It is also compatible with several storage devices such as CF card, FLASH, hard disk and so on.In this paper, based on analyzing the basic character of file systems of DOS and UNIX, we present the design principle according to the request of the military embedded GIS file system. Whereafter we introduce the realization method of the file system and enumerate the measures to ensure the reliability, compatibility and expansibility of the file system. At last we give the result analysis and brief introduction to work afterwards. |
