3484 enhance and document tail follow support
Reviewed by: Joshua M. Clulow <jmc@joyent.com>

@@ -25,12 +25,23 @@
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
  */
+/*
+ * Copyright (c) 2013, Joyent, Inc. All Rights Reserved.
+ */
 
 
+#ifndef EXTERN_H
+#define EXTERN_H
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <port.h>
+
+
 #define WR(p, size) do { \
         if (write(STDOUT_FILENO, p, size) != (ssize_t)size) \
                 oerr(); \
         } while (0)
 

@@ -46,10 +57,11 @@
 
 struct file_info {
         FILE *fp;
         char *file_name;
         struct stat st;
+        file_obj_t fobj;
 };
 
 typedef struct file_info file_info_t;
 
 enum STYLE { NOTSET = 0, FBYTES, FLINES, RBYTES, RLINES, REVERSE };

@@ -65,5 +77,7 @@
 void oerr(void);
 int mapprint(struct mapinfo *, off_t, off_t);
 int maparound(struct mapinfo *, off_t);
 
 extern int Fflag, fflag, qflag, rflag, rval, no_files;
+
+#endif  /* EXTERN_H */