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.
4. Describe priority scheduling algorithm. Consider the following set of processes. Show the order in which the algorithm will schedule these processes. Assume preemptive and non-p
Determining the time quantum for a job is a critical task. Given the assumptions that the average switching time between processes is s, and the average amount of time an I/O bo
Compare user threads and kernel threads. User threads:- User threads are supported above the kernel and are executed by a thread library at the user level. Thread creation
Write a short note on disk scheduling One of the responsibities of operating system O/S is to use the hardware efficiently. Whenever a process requires I/O to or from the
Write a note on the usage of semaphores. Semaphore is a synchronization tool and it is a variable having integer values. It is accessed only by two standard atomic operations w
In modern operating systems, applications do not directly access the physical memory. Instead, they use so-called virtual memory, where each virtual address is translated to a phys
shell script that accepts two directory names as arguments and delete those file in the second directory that are identical to the file in the first
why we say" OS is a resource allocator" and “OS is a control program"?
Contiguous allocation: Every file will be allocated contiguous space in the memory. Allow the block size be 1K If a 50K files desires to be allocated space after t
Determine what the “blocking factor” of a file is Blocking factor is the number of logical records in one physical record
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