Explain the advantage of copy-on-write region copying for UNIX, where a call to fork is typically
followed by a call to exec. What should happen if a region that has been copied using copy-on
write is itself copied?
What will be an ideal response?
It would be wasteful to copy the forked process’s address space contents, since they are immediately replaced.
With copy-on-write, only those few pages that are actually needed before calling exec will be copied.
Assume now that exec is not called. When a process forks, its child may in turn fork a child. Call these the
parent, child and grandchild. Pages in the grandchild are logically copied from the child, whose pages are in
turn logically copied from the parent. Initially, the grandchild’s pages may share a frame with the parent’s
page. If, say, the child modifies a page, however, then the grandchild’s page must be made to share the child’s
frame. A way must be found to manage chains of page dependencies, which have to be altered when pages are
modified.
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Using the ________ feature to broadcast your current location can alert any potential stalkers where to find you or tell potential burglars that your house is currently empty
Fill in the blank(s) with correct word
To modify a slide master, you begin by clicking the Slide Master button in the:
A) Masters group on the Design tab. B) Presentation Views group on the Design tab. C) Presentation Views group on the View tab. D) Masters group on the View tab.
The ____ is the value that the wireless devices use to decrypt broadcast messages from APs.
A. GTK B. MK C. PTK D. PMK
A technician needs to install software onto company laptops to protect local running services, from external threats. Which of the following should the technician install and configure on the laptops if the threat is network based?
A. A cloud-based antivirus system with a heuristic and signature based engine B. A network based firewall which blocks all inbound communication C. A host-based firewall which allows all outbound communication D. A HIDS to inspect both inbound and outbound network communication