Added the syscalls for sys_read_dir(), and sys_rewind_dir().

sys_read_dir() now has a parameter for the maximum number of dirents that
are handled by the upper layer - which is currently 1.
Added a comment in fd.h to ease the location of the sys|user prototypes
of the corresponding functions in fd.c.


git-svn-id: file:///srv/svn/repos/haiku/trunk/current@58 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/os/kernel/dirent.h

@@ -21,11 +21,9 @@ typedef struct dirent {
 	char			d_name[1];
 } dirent_t;
 
-// ToDo: this structure is still incompatible with BeOS
 typedef struct {
 	int				fd;
-	struct dirent  *ent;
-	struct dirent   me;
+	struct dirent	ent;
 } DIR;
 
 #ifndef MAXNAMLEN