Each of these functions assumes that the user address has already been
verified to be below @code{PHYS_BASE}. They also assume that you've
-modified @func{page_fault} so that a page fault in the kernel causes
-@code{eax} to be set to 0 and its former value copied into @code{eip}.
+modified @func{page_fault} so that a page fault in the kernel merely sets
+@code{eax} to 0 and copies its former value into @code{eip}.
@node Project 2 Suggested Order of Implementation
@section Suggested Order of Implementation
File descriptors numbered 0 and 1 are reserved for the console: fd 0
is standard input (@code{stdin}), fd 1 is standard output
-(@code{stdout}). These special file descriptors are valid as system
-call arguments only as explicitly described below.
+(@code{stdout}). The @code{open} system call will never return either
+of these file descriptors, which are valid as system call arguments only
+as explicitly described below.
+
+Each process has an independent set of file descriptors. File
+descriptors are not inherited by child processes.
Consider implementing this function in terms of @func{filesys_open}.
@end deftypefn