From an original README by James Strickland, author of this implementation of diff. Files in this directory ----------------------- Jamfile - for building with 'jam' README - this file diff.cc - simple interface for doing diffs diff.h - " diffan.cc - diff analyzer, the hard part diffan.h - " diffsp.cc - diff Sequence, crunches a single file diffsp.h - " difftest.cc - simple test harness for a diff program External Dependencies --------------------- These files rely on the (read) file access routines provided by RcsFile, as defined in rcsfio.h. These files also use stdhdrs.h, a wrapper for system header files that uses #define's to determine what to include. Mostly all that are needed are the very common headers (stdio.h, string.h, stdlib.h) and the types header (sys/types.h). Debugging --------- Note that there are a number of #if DEBUGLEVEL > n .... debugging output .... #endif blocks in the code. If DEBUGLEVEL is not defined, then it is #define'd to be zero. DEBUGLEVEL=1 produces a reasonable amount of output (summary information such as #lines). What do they do? ---------------- p4diff (difftest.cc) provides the same style of output as GNU diff. The output is often identical to that of diff(1), although sometimes this implementation picks a different edit sequence.