Fully implement vfork. Vfork is now much much faster than even our

	fork. (On my machine, fork is about 240usecs, vfork is 78usecs.)

Implement rfork(!RFPROC !RFMEM), which allows a thread to divorce its memory
	from the other threads of a group.

Implement rfork(!RFPROC RFCFDG), which closes all file descriptors, eliminating
	possible existing shares with other threads/processes.

Implement rfork(!RFPROC RFFDG), which divorces the file descriptors for a
	thread from the rest of the group.

Fix the case where a thread does an exec.  It is almost nonsense for a thread
	to modify the other threads address space by an exec, so we
	now automatically divorce the address space before modifying it.

1 files changed, 3 insertions, 1 deletions

diff --git a/sys/kern/kern_exec.c b/sys/kern/kern_exec.c
index 8c88134..9c6f111 100644
--- a/sys/kern/kern_exec.c
+++ b/sys/kern/kern_exec.c
@@ -23,7 +23,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- *	$Id: kern_exec.c,v 1.58 1997/04/11 23:37:23 dyson Exp $
+ *	$Id: kern_exec.c,v 1.59 1997/04/12 04:07:50 dyson Exp $
  */
 
 #include <sys/param.h>
@@ -58,6 +58,8 @@
 #include <vm/vm_kern.h>
 #include <vm/vm_extern.h>
 
+#include <sys/user.h>
+
 #include <machine/reg.h>
 
 static int *exec_copyout_strings __P((struct image_params *));