Linux Kernel Architecture

Mauerer runapp02.tex V2 - 09/04/2008 6:09pm Page 1161

Appendix B: Working with the Source Code

B.4.1 LXR

LXR is a cross-referencing tool. It analyzes the kernel sources and generates a hypertext representation

in HTML for viewing in a browser. LXR lets users search on variables, functions, and other symbols, and

supports branching to their definitions in the source code as well as listing all points at which they are

used.Thisisusefulwhentracingcodeflowpathsinthe kernel. Figure B-4 shows how the source text is

displayed in the web browser.

Figure B-4: Linux source text as LXR-generated hypertext.

A web browser and a web server, preferably Apache, are needed to use LXR locally. Theglimpsesearch

engine is also required to search the sources for random strings.

The canonical version of LXR can be downloaded fromsourceforge.net/projects/lxr. Unfortunately,

this version has not seen any development for a number of years, and although the code works just fine,

it misses a number of features present in modern web applications.