README

This projects contains two little fuzzers:

fd_fuzz is a single-threaded stress test for the UNIX file I/O layer

file_fuzz is a single-threaded stress test for the C streams layer

Both are intended to operate differentially: run them with the same
seed on two different implementations and diff their output.

Both tools contain a number of caveats and limitations and
compile-time configuration options embedded in their source
code. You'll want to read the code before using these. They are quick
and dirty.

Both tools are designed to be a bit conservative, avoiding areas of
the respective standards that are highly underspecified. For example
file_fuzz avoids opening two FILEs that refer to the same on-disk file
because on some platforms (OS X in particular) there does not seem to
be any way to sync up the cached file information with the on-dis
information, rendering meaningful testing impossible.

N.B. if you want to compare two different runs, the initial contents
of the files data-0, data-1, etc. must be the same on both machines.
These files need not exist.