1. It 600 Operating System Midterm
IT–600 Operating Systems Midterm
Name: SRAVANI TADEPALLI
Date: 09/30/2014
1. What is the definition of an Operating System?
ANSWER: Operating system exist on the grounds that they offer a sensible approach to tackle the issue of making a usable processing
framework. The major objective of computer systems is to execute user programs and to make user issues simpler. Computer hardware
is developed to this objective. Since exposed hardware alone is not simple to utilize, application programs are produced. These programs
require basic operations, for example, those controlling the I/O devices. The regular capacities of controlling and assigning assets are
then brought together into one bit of software: the operating system. Another way we ... Show more content on Helpwriting.net ...
It 's very less prone when compared to apple. It is also vulnerable to virus. Disadvantages of LINUX is, it is complicated which needs
good deal of computer knowledge, less compatible which have less programs and games as windows have many programs. There are
less vendors selling LINUX computers.
WINDOWS: It is more compatible, good technical support , also huge quantity of function. Cons of windows are we need to buy anti–
virus program to protect from viruses, windows vista and 7 are very slow and also requires lot of memory, processor, disc space and is
much expensive.
APPLE: It is virus protective and more reliable it runs on apple computers which are less prone to hardware and software crash. Cons of
apple are, it is more expensive than windows, only available on apple computers, only few programs run on Mac, so less compatibility.
3. How is the difference between a single processor and a multi processor computer?
ANSWER: Single processor has one real processor, whereas multiprocessor framework has many real processors, both can have more
than one center for every processor. Multiprocessors which are a part of the system need a great deal of handling force. These systems
have been costly and not required by ordinary home or office clients. As the usage increased it became normal that one processor has 2,
3, 4 or
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2.
3. Nt1310 Unit 1 Review Sheet
#include #include "mlist.h" #define HASHSIZE 100000; int size = HASHSIZE; int ml_verbose=0; typedef struct mlnode { struct
mlnode *nextEntry; MEntry *currentEntry; int initiated; } bucket; struct mlist { int size; bucket **hashIndex; }; /** Creating a mailing
list with ml_create(). It uses calloc & malloc for memory allocation, relying on bucket pointers for assignment. (1.) Declaration of
pointers and variable 'i' for loop purpose. (2.) Print statement with "if verbose". Followed by malloc to allocate space for mlist pointer.
(3.) Initalize the first bucket pointer and assigning memory using calloc (allows memory space '0' to be assigned to the very first
bucket). (4.) Subsequently, check if any sub buckets exists, allocate ... Show more content on Helpwriting.net ...
It uses two bucket pointes to differentiate exsiting and newly add entries. Return values of each section, 1 being sucessful and 0 being
unsuccessul. (1.) Declaration of variable and pointers (2.) Call for a function look up to see if there is any matching entries. If no, return
value '1'.(3.) Set memory for newly declared pointer, "bucketNew". And if "bucketNew" is empty, set "null" to bucketNew–>nextEntry.
(4.) Set a hashindex for each bucket entry. (5.) Set "buckPresent = buckPresent–>nextEntry" until no more "buckPresent–>nextEntry"
exists. (6.) Set next to an empty bucket, and the entry to mentry **/ int ml_add(MList **ml, MEntry *me) { // No. 1 MList *l = *ml;
bucket *buckPresent; bucket *bucketNew; unsigned long hashval; int i; // No. 2 if (ml_lookup(l, me) != NULL) return 1; // No. 3
bucketNew = (bucket *) malloc(sizeof(bucket));
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4.
5. Run-Time Array Bound Checking Essay
A Review of Run–Time Array Bound Checking Techniques Shaan Shetty School of Electrical and Computer Engineering Cornell
University, Ithaca NY srs383@cornell.edu ABSTRACT C has been the most popular programming language for the last several decades
due to its simplicity and superior performance. Due to this reason, most legacy software is in C. But in recent times, several breaches in
security and reliability have been found to occur due to lack of memory safety of the C programming language. Memory–corruption
bugs in programs can breach security, and faults in kernel extensions can bring down the entire operating system. Modern languages
such as C# and Java enforce memory safety and hence prevent these security vulnerabilities. ... Show more content on Helpwriting.net
...
Austin, Scott E. Breach, and Gurindar S. Sohi [1]. The idea here is to augment the pointer representation in memory with the bounds of
the pointer's target. Spatial safety is enforced by checking these bounds whenever a pointer is dereferenced. These fat pointers consist of
the following parameters, value: The value of the safe pointer; it may contain any expressible address., base and size: The base address
of the referent and its size in bytes, storageClass: The storage class of the allocation, either Heap, Local, or Global., capability: When
dynamic variables are created, either through explicit storage allocation (e.g., calls to malloc()) or through procedure invocations (i.e., a
procedure call creates the local variables in the stack frame of the procedure), a unique capability is issued to that storage allocation. The
value attribute is the only safe pointer member that can be manipulated by the program source; all other members are inaccessible. base
and size are the spatial attributes. storageClass and capability are the temporal attributes. 1.2 CCured CCured is a program
transformation system that adds memory safety guarantees to C programs. It was proposed by George C. Necula, Jeremy Condit,
Matthew Harren, Scott Mcpeak, and Westley Weimer[2]. This approach classifies pointers as WILD, SEQ and SAFE depending on their
usage modes. Pointers which require null check before dereference are classified as
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6.
7. Notes On Hiv And Tb Newtb
#include #include #include #include #include "textbuffer.h" typedef struct textNode *link; typedef struct textbuffer{ link first; int lines;
}_textbuffer; typedef struct textNode{ link next; char *string; }_textNode; static link newNode(char *array); /* Allocate a new
textbuffer whose contents is initialised with the text given * in the array. */ TB newTB (char text[]) { TB newBuffer =
malloc(sizeof(struct textbuffer)); newBuffer–>first = NULL; newBuffer–>lines = 0; link curr = newBuffer–>first; link new = NULL;
char *temp = malloc(sizeof(char)*(1+strlen(text))); char *newLine = NULL; strcpy(temp, text); newLine = strtok(temp," "); while
(newLine != NULL) { new = newNode(newLine); int str_len = strlen(new–>string); new–>string[str_len] = ' '; new–>string[str_len+1]
= ' '; if (newBuffer–>first == NULL) { newBuffer–>first = new; } else { curr–>next = new; } curr = new; newBuffer–>lines++; newLine
= strtok(NULL," "); } return newBuffer; } static link newNode(char *array) { link Node = malloc(sizeof(struct textNode)); Node–
>string = malloc(sizeof(char)*(strlen(array))); strcpy(Node–>string,array); Node–>next = NULL; return Node; } /* Free the memory
occupied by the given textbuffer. It is an error to access * the buffer afterwards. */ void releaseTB (TB tb)
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11. Vhdl
Verilog HDL: A Guide to Digital Design and Synthesis, Second Edition By Samir Palnitkar Publisher: Prentice Hall PTR Pub Date:
February 21, 2003 ISBN: 0–13–044911–3 Pages: 496
Written for both experienced and new users, this book gives you broad coverage of Verilog HDL. The book stresses the practical design
and verification perspective ofVerilog rather than emphasizing only the language aspects. The informationpresented is fully compliant
with the IEEE 1364–2001 Verilog HDL standard. Describes state–of–the–art verification methodologies Provides full coverage of gate,
dataflow (RTL), behavioral and switch modeling Introduces you to the Programming Language Interface (PLI) Describes logic
synthesis methodologies Explains ... Show more content on Helpwriting.net ...
X Window System is a trademark of X Consortium, Inc. The publisher offers discounts on this book when ordered in bulk quantities.
For more information, contact: Corporate Sales Department, Prentice Hall PTR, One Lake Street, Upper Saddle River, NJ 07458.
Phone: 800–382–3419; FAX: 201– 236–7141. E–mail: corpsales@prenhall.com. Production supervisor: Wil Mara Cover designer: Nina
Scuderi Cover design director: Jerry Votta Manufacturing manager: Alexis R. Heydt–Long Acquisitions editor: Gregory G. Doench
Printed in the United States of America 10 9 8 7 6 5 4 3 2 1 SunSoft Press A Prentice Hall Title
4
Dedication
To Anu, Aditya, and Sahil, Thank you for everything. To our families, Thank you for your constant encouragement and support. ―
Samir
5
About the Author
Samir Palnitkar is currently the President of Jambo Systems, Inc., a leading ASIC design and verification services company which
specializes in high–end designs for microprocessor, networking, and communications applications. Mr. Palnitkar is a serial entrepreneur.
He was the founder of Integrated Intellectual Property, Inc., an ASIC company that was acquired by Lattice Semiconductor, Inc. Later
he founded Obongo, Inc., an e–commerce software firm that was acquired by AOL Time Warner, Inc. Mr. Palnitkar holds a Bachelor of
Technology in Electrical Engineering from Indian Institute of Technology,
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12.
13. Lab #1
Computer science department Data security – Lab # 1 Lab Description Set–UID is an important security mechanism in Unix operating
systems. When a Set–UID program is run, it assumes the owner's privileges. For example, if the program's owner is root, then when
anyone runs this program, the program gains the root's privileges during its execution. Set–UID allows us to do many interesting things,
but unfortunately, it is also the culprit of many bad things. Therefore, the objective of this lab is two–fold: Appreciate its good side:
understand why Set–UID is needed and how it is implemented. Be aware of its bad side: understand its potential security problems. Lab
Tasks This is an exploration lab. Your main task is to ... Show more content on Helpwriting.net ...
You should perform whatever work requires the additional privileges as early in the program as possible, and you should drop the extra
privileges immediately after that work is done. While many programmers may be aware of the need to drop privileges, many more are
not. Worse, those who do know to drop privileges rarely know how to do so properly and securely. Dropping privileges is tricky
business because the semantics of the system calls to manipulate IDs for setuid/setgid vary from one Unix variant to another–sometimes
only slightly, but often just enough to make the code that works on one system fail on another. On modern Unix systems, the extra
privileges resulting from using the setuid or setgid bits on an executable can be dropped either temporarily or permanently. It is best if
your program can do what it needs to with elevated privileges, then drop those privileges permanently, but that's not always possible. If
you must be able to restore the extra privileges, you will need to be especially careful in your program to do everything possible to
prevent an attacker from being able to take control of those privileges. We strongly advise against dropping privileges only temporarily.
You should do everything possible to design your program such that it can drop privileges permanently as quickly as possible. We do
recognize that it's not
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14.
15. Trinode
#include (–– removed HTML ––) #include (–– removed HTML ––) #include (–– removed HTML ––) #include (–– removed HTML ––)
#include "TriePrediction.h" //Creates/inserts words to my trie TrieNode *createNode() { int i; TrieNode *new =
malloc(sizeof(TrieNode)); for (i = 0; i < 26; i++) { new–>children[i] = NULL; } new–>subtrie = NULL; new–>count = 0; //new–
>subtrie–>children[i] = NULL //printf("I got here"); return new; } //This function goes to the end of the string and checks if there //is
some punctuation. If so, it returns a flag. int checkPunctuation(char *inputString) { //char *str; int length = strlen(inputString); //str =
malloc(sizeof(inputString) + 1); //strcpy(str, inputString); if(inputString[length–1] ... Show more content on Helpwriting.net ...
TrieNode *buildTrie(char *filename) { TrieNode *root; TrieNode *holder; TrieNode *temp = NULL; char inputTest[1025]; char
str[1026]; char *str2; char *toFree; char buffer[1025]; char previousWord[1025]; FILE *file; file = fopen(filename, "r"); root =
createNode(); strcpy(previousWord, ""); while(fscanf(file, "%s", inputTest) != EOF) { //We need to make everything lowercase letters
and remove //other symbols. strcpy(str, inputTest); stripPunctuation(str); //This a flag that checks for punctuation. //If it is 1, then we
want to make sure it has a different //insertion algorithm if(checkPunctuation(inputTest) == 1) { if(temp == NULL) insertToTrie(root,
str, 0); else { insertToTrie(root, str, 0); if(temp–>subtrie == NULL) temp–>subtrie = createNode(); insertToTrie(temp–>subtrie, str, 0);
temp = NULL; } //printf("Inserting to subtrie (has punctuation)... %sn", str); //This helps to take care of double punctuation words,
where
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16.
17. Mac Os X
Apple's Macintosh OSX Panther
CS555 Section 3
Tomomi Kotera
Table of Contents
Table of Contents ................................................................ Page 1
Introduction ....................................................................... Page 2
Overview ...........................................................................Page 2
CPU Scheduling ...................................................................Page 3
Symmetric Multiprocessing (SMP) ............................................Page 5
Memory Protection ................................................................Page 6
Virtual Memory ....................................................................Page 7
Technical and Commercial Success of Mac OS X ..........................Page 11
Conclusion ...........................................................................Page 13
Bibliography....................................................................... Page 14
Introduction
The Mac OS X Panther operation system has met with both ... Show more content on Helpwriting.net ...
Mach maintains the register state of its threads and schedules them preemptively in relation to one another. In general, multitasking may
be either cooperative or preemptive. Classic Mac OS implements cooperative multitasking which was not very intelligent. In
cooperative CPU scheduling the OS requires that each task voluntarily give up control so that other tasks can execute, so unimportant
but CPU–intensive background events might take up so much for a processor's time that more important activities in the foreground
would become sluggish and unresponsive. On the other hand, preemptive multitasking allows an external authority to delegate execution
time to the available tasks. Mac OS X's Mach supports preemptive multitasking in which it processes several different tasks
simultaneously.
To affect the structure of the address space, or to reference any resource other than the address space, the thread must execute a special
trap instruction which causes the kernel to perform operations on behalf of the thread, or to send a message to some agent on behalf of
the thread. In general, these traps manipulate resources associated with the task containing the thread.
Mach provides a flexible framework for thread scheduling policies. Mac OS X supports both the multilevel feedback queue scheduling
and round–robin (RR) scheduling algorithm. The multilevel feedback queue scheduling
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18.
19. Smartarray Essay
#include #include #include #include "SmartArray.h" // this creates a smart array pointer // our code should create an array that
dynamically increases or decreases SmartArray *createSmartArray(int length) { int n=0, i, capacity; // Dynamically allocate space for a
new SmartArray SmartArray *smarty; char **temp; temp = NULL; smarty = malloc(sizeof(SmartArray)); if(smarty==NULL) return
NULL; smarty–>size = 0; // Initialize its internal array to be of length length or // DEFAULT_INIT_LEN if(length
DEFAULT_INIT_LEN ) { temp = malloc(sizeof(char * ) * length); n = length; } smarty–>capacity = n; if (temp == NULL) return
NULL; smarty–>array=temp; // initialize pointers in the array to NULL for (i=0; iarray[i] = NULL; ... Show more content on
Helpwriting.net ...
LL; if(str==NULL) return NULL; size = smarty–>size; capacity = smarty–>capacity; slen = strlen(str); // expands the array if full // but
really just creates an array of capacity*2 +1 and destroys old if (size==capacity) { expandSmartArray( smarty, (capacity * 2 + 1)); }
tempVar = malloc(sizeof(char) * (slen+1)); if(tempVar==NULL) return NULL; strcpy(tempVar, str); smarty–>array[size] = tempVar; if
(str== NULL||smarty–>array== NULL||smarty==NULL) return NULL; smarty–>size = size + 1; // return the contents of string pointer
return smarty–>array[size]; } // expands smartArray to size of length SmartArray *expandSmartArray(SmartArray *smarty, int length) {
int i, cap, si; char **tempArray; if(smarty==NULL) return NULL; if(smarty–>array==NULL) return NULL; tempArray=NULL; si =
smarty–>size; cap = smarty–>capacity; if(length array[i]; } for (i=si; iarray); // copies the temp array address to the old array smarty–
>array = tempArray; smarty–>capacity = length; printf("–> Expanded SmartArray to size %d.n", length); } else { return NULL; }
return smarty; } // returns the element at the index // this function protects the user from going out of bounds with the array char
*get(SmartArray *smarty, int index) { // if index was out of bounds or if the smarty pointer was null if((index < 0) || (index > smarty–
>capacity)|| smarty==NULL) return NULL; return smarty–>array[index]; } // sets a string at the index indicated // if no
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20.
21. Dns Iterative Search Project Scenario
DNS ITERATIVE SEARCH PROJECT Student Name Course Title Professor Name University Name August 22nd, 2016 DNS
ITERATIVE SEARCH PROJECT INTRODUCTION TO THE PROJECT SCENARIO An iterative DNS search query is one in which a
DNS client permits the DNS server to give back the best answer it can give taking into account its reserve or zone information. On the
off chance that the questioned DNS server does not have an accurate match for the questioned name, the most ideal data it can return is a
referral (that is, a pointer to a DNS server legitimate for a lowermost level of the server DNS domain namespace). The DNS client can
then question the DNS server for which it got a referral. It proceeds with this procedure until it ... Show more content on Helpwriting.net
...
The subsequentprocedures will take place: 1. The client interacts "NameServer1"through a non–recursive query for "noam.reskit.com".
The server must now return either the answer or an error message. 2. NameServer1 firstly searches and checks its zones and cache for
the response, however does not discover it, so it contacts a server commanding for the Internet (which is a root server)by means of an
iterative dns query for "noam.reskit.com". 3. The server at the source of the network like online medium does not distinguish the
response, so it replies with a recommendation to a server commanding for the ".com domain". 4. NameServer1 links a server
commanding for the ".com domain"by way of an iterative query for "noam.reskit.com". 5. The server commanding for the ".com"
domain priory recognize the particularresponse, so it replies with an appointment to a dns server for the "reskit.com domain". 6.
NameServer1 associates the server commanding for the "reskit.com domain"through an iterative query especially for
"noam.reskit.com". 7. The server commanding for the "reskit.com" domain does recognize the response. It answers with the demanded
or searched out IP address. 8. NameServer1 replies to the "client iterative query"through the IP address for "noam.reskit.com"
(microsoft, 2016). SOURCE CODE FOR DNS ITERATIVE SEARCH QUERY //HEADER FILES #INCLUDE "WINSOCK2.H"
#INCLUDE "WINDOWS.H" #INCLUDE "STDIO.H" #INCLUDE "CONIO.H" #PRAGMA
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22.
23. Notes On Codes And Codes
/*s4304939 Assignment 4 CSSE2310 */ #include <stdio.h> #include <unistd.h> #include <stdlib.h> #include <string.h> #include
<signal.h> #include <sys/types.h> #include <sys/socket.h> #include <arpa/inet.h> #include <pthread.h> #include <stdio.h> #include
<signal.h> #include "deck.h" #include "herrs.h" #include "game.h" int accept_connections(int fds[], unsigned int count, struct sockaddr
*addr, socklen_t *addrlen, portList* ports); /* int accept_connections(int fds[], unsigned int count, struct sockaddr *addr, socklen_t
*addrlen, portList* ports); */ game_t* global_game = 0; bool sigshutdown = false; // Note, not closing the streams etc. // Instead all we
do is kill the other process, reap it // and wait for ... Show more content on Helpwriting.net ...
0 * sizeof(char)); gamesList* curr; curr = ports[0].games[0]; char* playerN = malloc(200 * sizeof(char)); player_t* p =
malloc(sizeof(player_t)); p–>active = true; p–>protected = false; p–>connected = true; p–>reaped = false; p–>connection =
connectionFd; p–>cards[0] = '0 '; p–>cards[1] = '0 '; p–>score = 0; //p–>playerName = playerName; read_from_tcp(client_sock,
playerN); read_from_tcp(client_sock, gameN); while (curr–>game–>gname != 0 && curr–>next != NULL && strcmp(curr–>game–
>gname, gameN) != 0) { curr = curr–>next; } if(curr–>game–>gname == 0) { curr–>game–>gname = gameN; curr–>game–>pcount =
4; if(gameN[0] == '2 ' || gameN[0] == '3 ') { curr–>game–>pcount = gameN[0] – '0 '; } curr–>game–>players = malloc(curr–>game–
>pcount * sizeof(player_t*)); curr–>game–>players[0] = p; curr–>game–>jplayer = 1; } else if (strcmp(curr–>game–>gname, gameN)
== 0) { curr–>game–>players[curr–>game–>jplayer] = p; curr–>game–>jplayer++; if(curr–>game–>jplayer == curr–>game–>pcount) {
player_t *help; for(int i = 0; i < curr–>game–>pcount; i++) { for(int j = curr–>game–>pcount – 1; j > i; j––) { if(strcmp(curr–>game–
>players[j]–>playerName, curr–>game–>players[j – 1]–>playerName) < 0) { help = curr–>game–>players[j]; curr–>game–>players[j]
= curr–>game–>players[j – 1]; curr–>game–>players[j – 1] = help; } } }
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24.
25. List Entry Method For Routing Table
//supriya
/********************************************************************** * file: sr_router.c * date: Mon Feb 18 12:50:42
PST 2002 * Contact: casado@stanford.edu * * Description: * * This file contains all the functions that interact directly * with the
routing table, as well as the main entry method * for routing. 11 * 90904102
**********************************************************************/
#include <stdio.h>
#include <assert.h>
#include <time.h>
#include "sr_if.h"
#include "sr_rt.h"
#include "sr_router.h"
#include "sr_protocol.h"
/*––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––– * Method: sr_init(void) * Scope: Global * *
Initialize the routing subsystem * ... Show more content on Helpwriting.net ...
r_hdr–>ether_type))
{
case ETHERTYPE_IP: assert(ethr_hdr); struct ip* ip_hdr=get_ip_hdr(packet); uint32_t dst_ip = ip_hdr–>ip_dst.s_addr; uint32_t
src_ip= ip_hdr–>ip_src.s_addr;
struct ip* ip_hdr1=get_ip_hdr(packet); uint32_t src2= ip_hdr1–>ip_src.s_addr; struct sr_ethernet_hdr* ethr_hd1 = (struct
sr_ethernet_hdr *) packet;
if (sr–>gateways[0].ip == 0)
{
sr–>gateways[0].ip = src2; sr–>gateways[0].iface = sr_get_interface(sr,interface); for (j = 0; j < ETHER_ADDR_LEN; j++) { sr–
>gateways[0].dest_addr[j] = ethr_hd1–>ether_shost[j];
}
}
struct sr_if * iface = sr–>if_list; while (iface) { if (ip_hdr–>ip_dst.s_addr == iface–>ip) break; iface = iface–>next; } int i; int j; int
result=0; printf(" source ip address= %s
", inet_ntoa(ip_hdr–>ip_src));
if(iface)
{
printf("Destination is Interface
");
if(ip_hdr–>ip_p == UDP_PROTOCOL ||ip_hdr–>ip_p == TCP_PROTOCOL) { send_icmp_message(sr, len, interface, packet,
ICMP_C_DEST_PORT_UNREACHABLE, 0); }
else { if( ip_hdr–>ip_ttl > 1) { ip_hdr–>ip_ttl = ip_hdr–>ip_ttl–1; setIPchecksum(ip_hdr);//sumit 15th oct send_icmp_message(sr, len,
interface, packet, ICMP_C_ECHO_REPLY, 0); } }
}
else{
26. for (i = 0; i < 4; i ++) {
if (sr–>servers[i].ip == dst_ip) {
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27.
28. SIG Interview Questions Essay
SIG Interview Questions 1. Torpedo question: 2 torpedoes, each with 1/3 probability of hitting/ sinking a ship 2. I have 20% chance to
have cavity gene. If I do have the gene, there is 51% chance that I will have at least one cavity over 1 year. If I don't have the gene, there
is 19% chance that I will have at least one cavity over 1 year. Given that I have a cavity in 6 months, what's the probability that I have at
least a cavity over 1 year? 3. What is the probability of 5 people with different ages siting in ascending or descending order at a round
table? 4. We are racing, and can at any time signal to the other that we would like to double our bet. We've put down 100 to start and
during the race I signal to you I want to double ... Show more content on Helpwriting.net ...
Also, cards worth less than 5 are now valued at $0. What is the maximum price you are now willing to pay for the game? 19. Marble
weighing questions 20. How many ways can 5 different people sit down at a round table? How many ways can 5 different people sit
down in a line of chairs? What if they were seated at a long table with exactly five seats (the 5 people will sit side by side)? 21. I want to
have a birthday party outside this weekend (i.e. need sunny weather). On Saturday, the chance of rain is 60 percent, sun 40 percent. On
Sunday, rain is 80 percent, sun is 20 percent. From there, the interviewer can ask an array of questions: What are the chances I can have
my party this weekend? If I have my party, what are the chances my party is on Saturday/Sunday? Variation: You can hold a party only
if there is no rain on either saturday or sunday. The probability of rain on a saturday is 80% and 60% for sunday. What is the probablity
you can hold a party at the weekend? Given that you held a party, what is the probability that that it rained at the weekend? 22. Two
blind men are carrying 3 pairs of red rocks and 3 pairs of white socks. They hit each other in the mall and have to redistribute the socks
so that they receive the same amount of each color they had before. They can't receive any outside help. How do they do it? 23. If i toss
3 pieces on a tic–tac–toe board at random, and I pay you $9 if
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32. Notes On Types And Types
// Martin Jacobs s4304939 – Assignment 4 #include <string.h> #include <stdio.h> #include <stdlib.h> #include <stdbool.h> #include
<unistd.h> #include <errno.h> #include <sys/types.h> #include <sys/socket.h> #include <arpa/inet.h> #include <netdb.h> #include
<pthread.h> #define NOCARD '– ' #define NOPLAYER –1 typedef enum { EXIT_NORMAL = 0, EXIT_USAGE = 1,
EXIT_PLAYNAME = 2, EXIT_INVGAME = 3, EXIT_INVSERVP = 4, EXIT_SERVFAILED = 5, EXIT_INVGAMEINFO = 6,
EXIT_BADSERVMSG = 7, EXIT_SERVLOSS = 8, EXIT_INPUTEND = 9, EXIT_SYSFAIL = 20 } CRESULT; /* Exit codes and
messages */ void exit_prog(CRESULT r) { switch(r) { case EXIT_NORMAL: ... Show more content on Helpwriting.net ...
char cards[2]; char** playerNames; //save the names of the other players int pcount; int myid; bool* protected; bool* active; int
inplay[8]; // for cards still available int fdServer; // save socket for connection to server FILE* log; } gamestate_t; /* function for
connecting to the server */ int
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33.
34. Chrome Os
[Target & Application]{ The Chrome OS is designed to work with only specific hardware produced by Google such as Chromebook. It
is created for user who spend most of the time on the Web. Hence, only a browser, a media player and a file manager are pre–installed
together with the Chrome OS. } [Scheduling]{ Chrome Operating System runs the Linux 3.4.6 kernel which utilizes the Completely Fair
Scheduler. This is to ensure fairness by allowing processes an equal share of the CPU. To do this, the scheduler keeps track of the
amount of time each process has had with the CPU using a virtual runtime. The Completely Fair Scheduler also allows group
scheduling. Group scheduling ensures that in situations where tasks spawn ... Show more content on Helpwriting.net ...
In rare cases this can cause an application to crash when it attempts to access non–existent memory that was over–committed during a
previous, apparently successful allocation. On other systems such an allocation might fail outright much sooner with an explicit malloc
failure return that could be detected.
==================================================================================================
} [Security]{ ++Safe Browsing++ With Safe Browsing technology enabled in Chrome, if you encounter a website suspected of
containing phishing or malware as you browse the web, you will see a warning page. A phishing attack takes place when someone
masquerades as someone else to trick you into sharing personal or other sensitive information with them, usually through a fake website.
Malware, on the other hand, is software installed on your machine often without your knowledge, and is designed to harm your
computer or potentially steal information from your computer. ++Sandboxing++ Chrome Operating System also utilizes Sandboxing to
maintain its security. A sandbox provide security by only allowing programs to run that are not going to alter unauthorized areas of the
operating system, machine, or private information. Therefore it helps prevent malware from installing itself on the computer, or using
what happens in one browser tab to affect other tabs. The sandbox adds an
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38. Windows Nt vs Unix as an Operating System
Windows NT vs Unix As An Operating System
In the late 1960s a combined project between researchers at MIT, Bell Labs and
General Electric led to the design of a third generation of computer operating system known as MULTICS (MULTiplexed Information
and Computing Service). It was envisaged as a computer utility, a machine that would support hundreds of simultaneous timesharing
users. They envisaged one huge machine providing computing power for everyone in Boston. The idea that machines as powerful as
their GE–645 would be sold as personal computers costing only a few thousand dollars only 20 years later would have seemed like
science fiction to them.
However MULTICS proved more difficult than imagined to implement and Bell Labs
withdrew ... Show more content on Helpwriting.net ...
Most of these systems were (and still are) neither source nor binary compatible with one another, and most are hardware specific.
With the emergence of RISC technology and the breakup of AT&T, the UNIX systems category began to grow significantly during the
1980s. The term "open systems" was coined. Customers began demanding better portability and interoperability between the many
incompatible UNIX variants. Over the years, a variety of coalitions (e.g. UNIX International) were formed to try to gain control over
and consolidate the UNIX systems category, but their success was always limited.
Gradually, the industry turned to standards as a way of achieving the portability and interoperability benefits that customers wanted.
However, UNIX standards and standards organisations proliferated (just as vendor coalitions had), resulting in more confusion and
aggravation for UNIX customers.
The UNIX systems category is primarily an application–driven systems category, not an operating systems category. Customers choose
an application first–for example, a high–end CAD package–then find out which different systems it runs on, and select one. The final
selection involves a variety of criteria, such as price/performance, service, and support. Customers generally don't choose UNIX itself,
or which UNIX variant they want. UNIX just comes with the package when they buy a system to run their chosen
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39.
40. Distributed System Problem Solution Andrew Taneebaum &...
DISTRIBUTED SYSTEMS PRINCIPLES AND PARADIGMS PROBLEM SOLUTIONS ANDREW S. TANENBAUM MAARTEN
VAN STEEN Vrije Universiteit Amsterdam, The Netherlands PRENTICE HALL UPPER SADDLE RIVER, NJ 07458 SOLUTIONS
TO CHAPTER 1 PROBLEMS 1. Q: What is the role of middleware in a distributed system? A: To enhance the distribution transparency
that is missing in network operating systems. In other words, middleware aims at improving the single–system view that a distributed
system should have. 2. Q: Explain what is meant by (distribution) transparency, and give examples of different types of transparency. A:
Distribution transparency is the phenomenon by which distribution aspects in a system are hidden from users and applications. ... Show
more content on Helpwriting.net ...
If the microkernel has networking capabilities, there is also no principal objection in placing those servers on remote machines (which
run the same microkernel). 13. Q: Explain the principal operation of a page–based distributed shared memory system. A: Page–based
DSM makes use of the virtual memory capabilities of an operating system. Whenever an application addresses a memory location that is
currently not mapped into the current physical memory, a page fault occurs, giving the operating system control. The operating system
can then locate the referred page, transfer its content over the network, and map it to physical memory. At that point, the application can
continue. PROBLEM SOLUTIONS FOR CHAPTER 1 3 14. Q: What is the reason for developing distributed shared memory
systems? What do you see as the main problem hindering efficient implementations? A: The main reason is that writing parallel and
distributed programs based on message–passing primitives is much harder than being able to use shared memory for communication.
Efficiency of DSM systems is hindered by the fact, no matter what you do, page transfers across the network need to take place. If pages
are shared by different processors, it is quite easy to get into a state similar to thrashing in virtual memory systems. In the end, DSM
systems can never be faster than message–passing solutions, and will generally be
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41.
42. Annotated Bibliography On Linear Data Structure
An introduction to linked list: a Review
Abstract
This paper describes about linear data structure i.e. linked list. Linked list is dynamic in nature means there is no need to know size of
data in advance. It is linear collection of data elements which may or may not be stored at consecutive memory location. In linked list
pointers are used for providing the linear order and each node is divided into parts for storing data and link part. This paper provides
only overview that how linked list was created and what are its advantages over another data structure. It also defines how data is stored
in linked list. What type of linked list can be? What basic operations can be performed on singly linked list? .And also tried to define
applications of data structure.
Introduction
Linked list was developed by Cliff Shaw, Allen Newell and Herbert A. Simon at RAND Corporation in year of 1955–1956. It was firstly
used in information processing language for artificial intelligence. There are many disadvantages of array as compare to linked list. First
is array is a static data structure and size have to define before use for example: int marks [10] here size of array have fixed of 10
elements. Second array stores only similar type of elements in integer value according to upper example it will store only integer value
and third one is in array insertion and deletion operation are very difficult for performing that operations huge amount of data have to
move upward and downward
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43.
44. Malloc Lab: Writing a Dynamic Storage Allocator
Fall 2008 Malloc Lab: Writing a Dynamic Storage Allocator Assigned: December 16, Due: December 28, 11:59PM
YanQiben 12.16 2008
YanQiben (072021029@fudan.edu.cn) is the lead person for this assignment.
1 Introduction
In this lab you will be writing a dynamic storage allocator for C programs, i.e., your own version of the malloc, free and realloc routines.
You are encouraged to explore the design space creatively and implement an allocator that is correct, efficient and fast.
2 Logistics
You may work in a group of up to one people. Any clarifications and revisions to the assignment will be posted on the course Web page.
3 Hand Out Instructions
Start by copying malloclab–handout.tar to a protected directory in which you plan to do your ... Show more content on Helpwriting.net
...
Similarly, if the old block is 8 bytes and the new block is 4 bytes, then the contents of the new block are identical to the first 4 bytes of
the old block. These semantics match the the semantics of the corresponding libc malloc, realloc, and free routines. Type man malloc to
the shell for complete documentation.
5 Heap Consistency Checker
Dynamic memory allocators are notoriously tricky beasts to program correctly and efficiently. They are difficult to program correctly
because they involve a lot of untyped pointer manipulation. You will find it very helpful to write a heap checker that scans the heap and
checks it for consistency. Some examples of what a heap checker might check are: Is every block in the free list marked as free? Are
there any contiguous free blocks that somehow escaped coalescing? Is every free block actually in the free list? Do the pointers in the
free list point to valid free blocks? Do any allocated blocks overlap? Do the pointers in a heap block point to valid heap addresses? Your
heap checker will consist of the function int mm check(void) in mm.c. It will check any invariants or consistency conditions you
consider prudent. It returns a nonzero value if and only if your heap is consistent. You are not limited to the listed suggestions nor are
you required to check all of them. You
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45.
46. Expion II : Kernel-Type Process Of The Opencl Program
SECTION III: EXAMPLE OpenCL PROGRAM Using OpenCL in programming is relatively straightforward. First, write a kernel–type
method in C; this is the code that will be run on a kernel. Next, identify the platform the code is running on, and the device it will
execute on within that platform. Then you must instantiate a context from the device and create an instance of the kernel (this is the
program). Next, send the kernel to the
The following is a very short program written in C++ that uses the OpenCL interface. Its purpose is to print the name and capabilities of
the device running it, and pass a string to the "demo" kernel. The Demo kernel fills the string with "CPE 186" and passes it back.
Demo.cl
__kernel void demo(__global char* ... Show more content on Helpwriting.net ...
Figure 3: Running the built project on the development environment
When run on the development environment, it was shown that OpenCL was run on a device called "Hawaii" (my development
environment's R9 390 graphics card) which has forty available compute units; and the string result was "CPE 186". Figure 4: Running
the built project on a laptop
When run on my laptop, it instead
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47.
48. Development of a 3D Game: High Concept
Development of a 3D Game: High Concept Introduction This project presents a mini–model of a 3D game in C++ using OGRE for
graphics. In this regard, this game uses a particular algorithm discussed in succeeding paragraphs to make it reusable thus, doing away
with multiple levels. The idea behind this is that once the player finishes the game, a new task is generated without repeating the same
one (Alexandrescu, 2001). This project is to assist in learning how to program using C++ and learning to use OGRE to draw; the game
is designed in a manner that it is winnable or losable depending on the player's prowess. This game borrows from Pong, but is different
in that, as it does not require the player to make rash and speedy decisions; in this game, the player will move as they see fit while taking
precaution to avoid falling or making the same move twice. As opposed to Pong, which trains the player to make fast decisions, this
game gives a player the time to consider their moves thus helping the player to become patient and considerate. However, the main low–
point of the game is that failure to jump makes the player lose the game. Game Scene Management After designing the game's functions
and classes, the file structure of the game is decided upon. For this game, there are two file structures for each class; header type of file
and the source type of file. According to this game, the header file holds the class definition and the inline member functions while the
source
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49.
50. C Language
The C programming language (often, just "C") is a general–purpose, procedural, imperative computer programming language developed
in the early 1970s by Dennis Ritchie for use on the Unix operating system. It has since spread to many other operating systems, and is
now one of the most widely used programming languages. C also has had a great influence on many other popular languages,[1]
especially [[C++]] which was originally designed as an enhancement to C. It is the most commonly used programming language for
writing system software,[2][3] though it is also widely used for writing applications. Though not originally designed as a language for
teaching, and despite its somewhat unforgiving character, C is commonly used in computer science ... Show more content on
Helpwriting.net ...
The relatively low–level nature of the language affords the programmer close control over what the program is doing, while allowing
solutions that can be specially tailored and aggressively optimized for a particular platform. This allows the code to run efficiently on
very limited hardware, such as mass–produced consumer embedded systems, which today are as capable as the general–purpose
machines originally used to implement C.
A number of the above missing features are available
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51.
52. High Performance Scientific Computing Project
/* * Main.cpp * Author : Nayan V. Mehta and Mohit Chhabra * Course : ME 766(High Performance Scientific Computing) * Project
Name : Image Dehazing using Dark Channel Prior in cuda * reference : http://research.microsoft.com/en–
us/um/people/jiansun/papers/Dehaze_CVPR2009.pdf * * */ /*includes*/ #include "globals.h" // Define Const int imageheight = 0;
//image Height int imagewidth = 0; //image Width int imagesize = 0; //total number of pixels int blockdim = 16; char in_name[100] =
"in.jpg"; char out_name[100] = "out.jpg"; char trans_name[100] = "trans.jpg"; char dark_name[100] = "dark.jpg"; char air_name[100] =
"air.jpg"; char gray_name[100] = "gray.jpg"; int debugPrint = 1; GpuTimer timer; void parseArgs(int argc, char * argv[]) { for (int i = 1;
i < argc; i++) { if (strcmp(argv[i], "––help") == 0) { printf( "usage: ––output for output ––input for input ––help for help. "); exit(1); }
else if (strcmp(argv[i], "––output") == 0) { i++; strcpy(out_name, argv[i]); DEB_PRINTF("output = %s ", out_name); } else if
(strcmp(argv[i], "––input") == 0) { i++; strcpy(in_name, argv[i]); DEB_PRINTF("input = %s ", in_name); } else { printf("use ––help to
see usage. "); exit(1); } } } void start_clock() { timer.Start(); } void stop_clock() { timer.Stop(); cout << "Time Cost: " <<
timer.Elapsed() << "ms" << endl; cout << endl; } //read from img_name Mat read_image(char * image) { Mat img =
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