Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Q. Consider a system that holds 5000 users. Presume that you want to allow 4990 of these users to be able to access one file.
a. How would you denote this protection scheme in UNIX?
b. Could you propose another protection scheme that is able to be used more effectively for this purpose than the scheme provided by UNIX?
Answer:
a. There are two processes for achieving this:
1. Create an access control record with the names of all 4990 users.
2. Put these 4990 users in one group as well as set the group access accordingly. This scheme can't forever be implemented since user groups are restricted by the system.
b. The universal access to records applies to every user unless their name appears in the access-control list with different access permission. With this scheme you merely put the names of the remaining ten users in the access control list but with no access privileges allowed.
Hierarchical paging method Most modern computer systems maintain a large logical-address space. In this situation the page table itself turns into excessively large. To remedy
Q. Polling for an I/O completion is able to waste a large number of CPU cycles if the processor iterates a busy-waiting loop several times before the I/O completes. However if the
Define UFD and MFD. In the two-level directory structure, every user has her own user file directory (UFD). Every UFD has a similar structure, but lists only the files of a one
Q. Explain some of the ways an application can use memory via the Win32 API. Answer: (1) Virtual memory offers several functions that allow an application to reserve and rele
what is the use of valid invalid bits in paging
Objectives 1. Login to UNIX system and logout 2. Learn features of the vi editor and to use online help (main pages). Gain experience using them to create a document
Determine the syntax of the Fork and Join Primitive Answer: Syntax of the Fork and Join Primitive is as follow: Fork Join
Consider a computer system with a 32-bit logical address and 4KB page size. The system supports up to 512MB of physical memory. How many entries are there in a conventional single-
Paging: Only the needed memory pages are moved to main memory from the swap machine for execution. Process size does not matter. Produce the concept of the virtual memory. It
Signal handling A signal is used in UNIX systems to inform a process that a particular event has occurred. 1. A signal is produced by the occurrence of a particular event.
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd