thie question has 4 parts a. Which of these describes the behavior of wait ()?(1)Terminates the calling process(2)Blocks the calling process until one of its children terminatesBlocks until input from the terminal arrives(3)(4) Blocks the calling process until all of its children have terminatedb. It is best to use malloc() to allocate space for an array when(1) You want to avoid the possibility of buffer overflow(2) You don't know the needed size until runtime, and it may vary a lot(3) A function needs to return a pointer to the array(4) The array must be read-onlyc. Three methods of communication between parent and child processes are ...(1) signal(), pause (), and wait ()(2) open(), dup2(), and 1seek ()(3)Wi-Fi, cellular, and cable(4) pipes, signals, and environment variablesd. If a process forks and the parent terminates before the child,(1) the child is forcibly terminated by the OS(2) the OS delivers SIGPARENT to the child(3) the "init" process (#1) adopts the child and is made its parent(4) the child is put in a kernel data structure calld the "orphanage"

wait() function does wait for the child process to complete and suspends any calling process in…

a. Which of these describes the behavior of wait ()? (1) Terminates the calling process (2) Blocks the calling process until one of its children terminates (3) Blocks until input from the terminal arrives (4) Blocks the calling process until all of its children have terminated b. It is best to use malloc() to allocate space for an array when (1) You want to avoid the possibility of buffer overflow (2) You don't know the needed size until runtime, and it may vary a lot A function needs to return a pointer to the array (3) (4) The array must be read-only c. Three methods of communication between parent and child processes are ... (1) signal(), pause (), and wait () (2) open (), dup2(), and 1seek () (3) Wi-Fi, cellular, and cable (4) pipes, signals, and environment variables

a. Which of these describes the behavior of wait ()? (1) Terminates the calling process (2) Blocks the calling process until one of its children terminates (3) Blocks until input from the terminal arrives (4) Blocks the calling process until all of its children have terminated b. It is best to use malloc() to allocate space for an array when (1) You want to avoid the possibility of buffer overflow (2) You don't know the needed size until runtime, and it may vary a lot A function needs to return a pointer to the array (3) (4) The array must be read-only c. Three methods of communication between parent and child processes are ... (1) signal(), pause (), and wait () (2) open (), dup2(), and 1seek () (3) Wi-Fi, cellular, and cable (4) pipes, signals, and environment variables

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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Assume that a virtual memory is managed using a buffer pool. The buffer pool contains five buffersand each buffer stores one block of data. Memory accesses are bydiskblock ID. Assume thefollowing series of memory accesses takes place: 5 2 5 12 3 6 5 9 3 2 4 1 5 9 8 15 3 7 2 5 9 10 4 6 8 5 For each of the following buffer pool replacement strategies, show the contents of the buffer poolat the end of the series, and indicate how many times a block was found in the buffer pool (insteadof being readinto memory). Assume that the buffer pool is initially empty b.Least frequently used (with counts kept only for blocks currently in memory, counts for a pageare lost when that page is removed, and the oldest item with smallestcount is removed whenthere is a tie). c.Least frequently used (with counts kept for all blocks, and the oldest item with the smallestcount is removed when there is a tie).
Assume that a virtual memory is managed using a buffer pool. The buffer pool contains five buffersand each buffer stores one block of data. Memory accesses are bydiskblock ID. Assume thefollowing series of memory accesses takes place: 5 2 5 12 3 6 5 9 3 2 4 1 5 9 8 15 3 7 2 5 9 10 4 6 8 5 For each of the following buffer pool replacement strategies, show the contents of the buffer poolat the end of the series, and indicate how many times a block was found in the buffer pool (insteadof being readinto memory). Assume that the buffer pool is initially empty a.First in, first out. b.Least frequently used (with counts kept only for blocks currently in memory, counts for a pageare lost when that page is removed, and the oldest item with smallestcount is removed whenthere is a tie). c.Least frequently used (with counts kept for all blocks, and the oldest item with the smallestcount is removed when there is a tie). d.Least recently used.
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