Make sure that directories can expand beyond their original size just
as any other file can.
-To take advantage of hierarchical name spaces in user programs,
-provide the following syscalls:
+Update the existing system calls so that, anywhere a file name is
+provided by the caller, an absolute or relative path name may used.
+Also, implement the following new system calls:
@table @code
@item SYS_chdir
generally more valuable to cache than data.) Document your
replacement algorithm in your design document.
+The provided file system code uses a ``bounce buffer'' in @struct{file}
+to translate the disk's sector-by-sector interface into the system call
+interface's byte-by-byte interface. It needs per-file buffers because,
+without them, there's no other good place to put sector
+data.@footnote{The stack is not a good place because large objects
+should not be allocated on the stack. A 512-byte sector is pushing the
+limit there.} As part of implementing the buffer cache, you should get
+rid of these bounce buffers. Instead, copy data into and out of sectors
+in the buffer cache directly. You will probably need some
+synchronization to prevent sectors from being evicted from the cache
+while you are using them.
+
In addition to the basic file caching scheme, your implementation
should also include the following enhancements: