Well, mount(8) is still disaster.  Already I have reports of two problems.

1) It won't compile.  This has the advantage that you'll never see any
other bugs, but it does reduce its usefulness somewhat.  The mount(2)
prototype I used in sys/mount.h and in the _syscall5 in mount.c doesn't
agree with <unistd.h>.  The easy fix is to comment out the prototype in
<unistd.h>, the better fix is to correct my prototypes by adding the
const qualifier to the final parameter of mount(2) in both places.

2) The root entry doesn't get added to the mtab when the mtab is missing.
This used to work right, and the patch below makes it work again.


--- 1.1	1992/09/06 13:30:53
+++ mount.c	1992/09/06 23:57:19
@@ -15,7 +15,7 @@
 #include <unistd.h>
 
 _syscall5(int, mount, const char *, special, const char *, dir,
-	   const char *, type, unsigned long, flags, void *, data);
+	   const char *, type, unsigned long, flags, const void *, data);
 #endif
 
 
--- 1.1	1992/09/06 13:30:53
+++ sundries.c	1992/09/06 23:57:20
@@ -153,6 +153,7 @@
       if (addmntent (F_mtab, fstab) == 1)
 	die (1, "mount: error writing %s: %s", MOUNTED, strerror (errno));
     }
+  endmntent (F_mtab);
 }
 
 /* Open mtab.  */
@@ -159,8 +160,10 @@
 void
 open_mtab (const char *mode)
 {
-  if ((F_mtab = setmntent (MOUNTED, mode)) == NULL)
+  if (fopen (MOUNTED, "r") == NULL)
     create_mtab ();
+  if ((F_mtab = setmntent (MOUNTED, mode)) == NULL)
+    die (2, "can't open %s: %s", MOUNTED, strerror (errno));
 }
 
 /* Close mtab.  */
--- sys/mount.h~	Sun Sep  6 08:22:57 1992
+++ sys/mount.h	Sun Sep  6 18:57:20 1992
@@ -113,7 +113,7 @@
 #ifdef HAVE_MOUNT5
 /* 0.96c-pl1 and later we have a five argument mount(2).  */
 int mount (const char *__special, const char *__dir,
-	   const char *__type, unsigned long __flags, void *__data);
+	   const char *__type, unsigned long __flags, const void *__data);
 #else
 /* Before 0.96c-pl1 we had a four argument mount(2).  */
 int mount (const char *__special, const char *__dir,