Figure 1 Ring Structures
|
|
- Andrea Lang
- 5 years ago
- Views:
Transcription
1 CS 460 Lab 10 The Token Ring I Tong Lai Yu ( The materials here are adopted from Practical Unix Programming: A Guide to Concurrency, Communication and Multithreading by Kay Robbins and Steven Robbins. ) 1 Introduction The ring topology is one of the simplest configurations for connecting communicating entities. A ring network topology connects each node to exactly two other nodes, forming a single continuous pathway for signals through each node. Data travels from node to node, with each node along the way handling every packet. Figure 1 illustrates two ring structures. Figure 1 Ring Structures Because a ring topology provides only one pathway between any two nodes, ring networks may be disrupted by the failure of a single link. A node failure or cable break might isolate every node attached to the ring. To overcome this vulnerability, many ring networks such as Spatial Reuse Protocol, Fiber Distributed Data Interface (FDDI), and Resilient Packet Ring, add a counter-rotating ring to form a redundant topology. In FDDI networks, when a break occurs, data are wrapped back onto the complementary ring before they reach the end of the cable, maintaining a path to every node along the resulting C-Ring. Some network protocols lik IEEE token bus avoid the weakness of a ring by physically arranging the nodes in a bus but logically forming a ring. This lab implements a ring of processes that communicate via pipes. Each process represents a node on the ring; it reads from standard input and writes to standard output. Process n 1 redirects its standard output to the standard input of process n through a pipe. The ring structure can be easily extended to simulate ring networks or implement algorithms for mutual exclusion and leader election. Before moving on, use the man command to study the following functions: e.g. man dup2 dup2 read write pipe fprintf atoi getpid wait 1
2 Exercise 0 Explain briefly in your own words what each of the above functions does. 2 Forming a Ring We shall use the system call dup2 to copy file descriptors to the appropriate entry of the file descriptor table. As shown below, the function takes two parameters, filedes1 and filedes2. It closes entry filedes2 of the file descriptor table and then copies the pointer of entry filedes1 into entry filedes2. #include <unistd.h> int dup2 ( int filedes1, int filedes2 ); The following code connects the standard output of a process to its standard input through a pipe and Figures 2-4 show the status of the process of after certain statements have been executed. The numbers in square brackets (e.g ) are indices of the process file descriptor table entry. The entries in the file descriptor table are pointers to entries in the system file table. For example, write in entry [4] means a pointer to the write entry in the system file table for. Figure 2 depicts the file descriptor table after has been created. A program can write to the pipe at this point using a file descriptor value of 4 in a write. #include <unistd.h> int fd[2]; pipe ( fd ); dup2 ( fd, STDIN_FILENO ); dup2 ( fd, STDOUT_FILENO ); [3] Figure 2 [2] ; [4] File descriptor table standard input standard output [3] read [4] write Status of Process After Execution of pipe (fd) [3] Figure 3 [2] [4] File descriptor table read write [3] read [4] write Status of Process After Execution of dup2 s 2
3 The instruction dup2 ( fd, STDIN FILENO ) does the following: 1. It closes the stdandard input file descriptor. 2. It makes file descriptor be a copy of fd. On the other hand dup2 ( fd, STDOUT FILENO ) closes the standard output file descriptor and makes it to be a copy of fd. Figure 3 shows the status of the file descriptor table after executing the two dup2 in the above code. At this point, the program can write to the pipe using a file descriptor value of either 1 or 4; it can read from the pipe using or [3]. Therefore, we can close [3] ( fclose ( fd ) ) and [4] ( fclose ( fd ) ). Figure 4 shows the status after descriptors 3 and 4 are closed. [2] File descriptor table read write Figure 4 Status of Process After Execution of close(fd) and close(fd) Exercise 1 What happens if, after connecting standard output to standard input via a pipe, the process of the above code executes the following code segment? Explain. int n = 98; for ( int i = 0; i < 10; i++ ) { write ( STDOUT_FILENO, &i, sizeof(i) ); read ( STDIN_FILENO, &n, sizeof (n) ); fprintf( stderr, "%d\n", n ); Exercise 2a What happens if the code in Exercise 1 is replaced by the following code? Explain. int n = 98; for ( int i = 0; i < 10; i++ ) { read ( STDIN_FILENO, &n, sizeof (n) ); write ( STDOUT_FILENO, &i, sizeof(i) ); fprintf( stderr, "%d\n", n ); Hint: The program hangs on the first read. Why? Exercise 2b What happens if the code in Exercise 1 is replaced by the following code? Explain. int n = 98; for ( int i = 0; i < 10; i++ ) { printf("%d ", i ); scanf ( "%d", &n ); fprintf( stderr, "%d\n", n ); Answers: The program hangs on scanf because the pipe reading and writing are fully buffered. The funciton printf does not write anything to the pipe until the buffer is full. Put a fflush ( std ) statement after the printf to get output. 3
4 We can create a ring of two processes using this piping technique as shown in the ring-twop.cpp program below: //ring-twop.cpp #include<unistd.h> using namespace std; int main() { int fd[2]; pipe ( fd ); dup2 ( fd, STDIN_FILENO ); dup2 ( fd, STDOUT_FILENO ); pipe ( fd ); if ( fork() ) //parent dup2(fd, STDOUT_FILENO); else //child dup2(fd, STDIN_FILENO); //parent redirects std output //child redirects std input The parent process of the code shown above redirects standard input through the first pipe to the standard output of the child and redirects standard output through the second pipe to standard input of the child. Exercise 3 Draw a diagram like those of Figures 2-4 to show the connections of the processes after the second pipe ( fd ) has been executed. Then draw a diagram after fork() but before the rest of the if statement, showing pipe x, pipe y, the two processes ( parent and child ) and the connections with file descriptors labeled along the edges. You may click on the link to see the answers. The function fork() of ring-twop.cpp creates a child process (suppose is the parent process and Y is the child process). The parent makes standard output be the copy of fd. The child process makes standard input be the copy of fd. It then closes both fd and fd. The final status of the pipes is shown in Figure 5. The parent process and the child process Y can now communicate via pipex x and y: sends messages to Y via pipe y and Y sends messages to via. 4
5 [2] Y pipe y Process fd table read pipe y write Process Y fd table pipe y read write Figure 5 [2] Status of Process (parent) and Y (child) at the end of code. The code of ring-twop.cpp shown above for forming a ring of two processes can be easily extended to rings of arbitrary size. The program ring.cpp shown in Listing 1 sets up a unidirectional ring of n processes where n is passed on the command line (and converted to the variable nprocess). A total of n pipes are required. Note, however, that the program only needs an array of size 2 rather than 2n to hold the file descriptors. Program Listing 1 Creating a Ring of Processes //ring.cpp #include <unistd.h> #include <string.h> #include <errno.h> #include <stdlib.h> #include <iostream> using namespace std; int main( int argc, char *argv[] ) { int fd[2]; int childpid; //process id of child int nprocs; //total number of processes in the ring int error; //return value from dup2 call int i; if ( argc < 2 (nprocs = atoi( argv)) <= 0 ){ cout << "Usage: " << argv << " nprocesses" << endl; if ( pipe ( fd ) == -1 ){ perror("could not create pipe"); if ( dup2 ( fd, STDIN_FILENO ) == -1 dup2 ( fd, STDOUT_FILENO ) == -1 ) { perror ("Could not dup pipes"); for ( i = 1; i < nprocs; i++ ) { 5
6 if ( pipe( fd ) == -1 ) { fprintf(stderr, "Could not create pipe %d: %s\n", i, strerror ( errno ) ); if ( ( childpid = fork() ) == -1 ) { fprintf(stderr, "Could not create child %d: %s\n", i, strerror ( errno ) ); if ( childpid > 0 ) //for parent, reassign stdout error = dup2 ( fd, STDOUT_FILENO ); else //for child, reassign stdin error = dup2 ( fd, STDIN_FILENO ); if ( error == -1 ) { fprintf(stderr, "Could not dup pipes for iteration %d: %s\n", i, strerror( errno ) ); if ( childpid ) //parent done break; //say hello to the world fprintf( stderr, "This is process %d with ID %d and parent ID is %d\n", i, getpid(), getppid() ); return 0; Exercise 4 1. Compile and run the program ring.cpp shown in Listing Create a Makefile to compile the program. 3. Run ring for several values of the command-line argument and observe what happens as the number of processes in the ring varies from 1 to Modify the original program by putting in a wait system call before the final fprintf statement. ( Name your program ring1. ) How does this affect the output of the program? 5. Modify the original program by putting in a wait system call after the final fprintf statement. ( Name your program ring2. ) How does this affect the output of the program? 6. Replace the fprintf statement in the original program, ring, with calls to sprintf and prtastr. ( Name your program ring3. ) write the function void prtastr( const char *s, int fd, int n ); which prints the s string one character at a time to the file specified specified by the descriptor fd using write. After each character is output, prtastr executes the following loop: for ( i = 0; i < n; i++ ); This loop just wastes some CPU time. Use prtastr to output the string to the standard error. The value of n is is passed as an optional command-line argument to ring3. The default value for this parameter is 1. Run the program with a value of n that causes a small, but barely noticeable, delay between the output of characters. 7. Extra Credit ( 2 points ). Modify ring1 to create a bidirectional torus of processes. Accumulate ID arrays to test connectivity. A torus has a two-dimensional structure. It is like a mesh except that the processes at the ends are connected together. The n 2 processes are arranged in n rings in each dimension. Each process has four connections ( North, South, East, and West ). 6
7 Write a report containing the following. 1. Solutions to all the exercises and questions with sample screen shots. 2. Comment on your work and state if you have finished the lab successfully. 7
IPC and Unix Special Files
Outline IPC and Unix Special Files (USP Chapters 6 and 7) Instructor: Dr. Tongping Liu Inter-Process communication (IPC) Pipe and Its Operations FIFOs: Named Pipes Ø Allow Un-related Processes to Communicate
More informationLecture 8: Unix Pipes and Signals (Feb 10, 2005) Yap
Lecture 8: Unix Pipes and Signals (Feb 10, 2005) Yap February 17, 2005 1 ADMIN Our Grader will be Mr. Chien-I Liao (cil217@nyu.edu). Today s Lecture, we will go into some details of Unix pipes and Signals.
More informationInter-Process Communication
CS 326: Operating Systems Inter-Process Communication Lecture 10 Today s Schedule Shared Memory Pipes 2/28/18 CS 326: Operating Systems 2 Today s Schedule Shared Memory Pipes 2/28/18 CS 326: Operating
More informationOS COMPONENTS OVERVIEW OF UNIX FILE I/O. CS124 Operating Systems Fall , Lecture 2
OS COMPONENTS OVERVIEW OF UNIX FILE I/O CS124 Operating Systems Fall 2017-2018, Lecture 2 2 Operating System Components (1) Common components of operating systems: Users: Want to solve problems by using
More informationChapter 3 Processes we will completely ignore threads today
Chapter 3 Processes we will completely ignore threads today Images from Silberschatz Pacific University 1 Process Define: Memory Regions: Loaded from executable file: ELF: Executable and Linkable Format
More informationUNIX Input/Output Buffering
UNIX Input/Output Buffering When a C/C++ program begins execution, the operating system environment is responsible for opening three files and providing file pointers to them: stdout standard output stderr
More informationMaria Hybinette, UGA. ! One easy way to communicate is to use files. ! File descriptors. 3 Maria Hybinette, UGA. ! Simple example: who sort
Two Communicating Processes Hello Gunnar CSCI 6730/ 4730 Operating Systems Process Chat Maria A Hi Nice to Hear from you Process Chat Gunnar B Dup & Concept that we want to implement 2 On the path to communication
More informationCS 350 : COMPUTER SYSTEM CONCEPTS SAMPLE TEST 2 (OPERATING SYSTEMS PART) Student s Name: MAXIMUM MARK: 100 Time allowed: 70 minutes
CS 350 : COMPUTER SYSTEM CONCEPTS SAMPLE TEST 2 (OPERATING SYSTEMS PART) Student s Name: MAXIMUM MARK: 100 Time allowed: 70 minutes Q1 (30 marks) NOTE: Unless otherwise stated, the questions are with reference
More informationCSci 4061 Introduction to Operating Systems. IPC: Basics, Pipes
CSci 4061 Introduction to Operating Systems IPC: Basics, Pipes Today Directory wrap-up Communication/IPC Test in one week Communication Abstraction: conduit for data exchange between two or more processes
More informationProcess Turnaround Time Total Wait Time P 1 12 ms 0 ms P 2 21 ms 12 ms P 3 23 ms 18 ms P 4 20 ms 17 ms
Name: SOLUTIONS Score: / 100 CSCI-4210/6140 Operating Systems Midterm Exam Thursday 10/9 1-PAGE (2-SIDED) CRIB SHEET ALLOWED; NO CALCULATOR ANSWER ALL QUESTIONS; USE EXTRA PAPER AS NECESSARY 1. [25 POINTS]
More informationCSC209H Lecture 7. Dan Zingaro. February 25, 2015
CSC209H Lecture 7 Dan Zingaro February 25, 2015 Inter-process Communication (IPC) Remember that after a fork, the two processes are independent We re going to use pipes to let the processes communicate
More informationUnix Basics Compiling and Using. CMPT 300 Operating Systems I Summer Segment 2: Unix Basics. Melissa O Neill
CMPT 300 Operating Systems I Summer 1999 Segment 2: Unix Basics Melissa O Neill Unix Basics Compiling and Using You had to learn how to do the basics on a Unix system, including: Look up a manual page
More informationProcess Creation in UNIX
Process Creation in UNIX int fork() create a child process identical to parent Child process has a copy of the address space of the parent process On success: Both parent and child continue execution at
More informationWeek 2 Intro to the Shell with Fork, Exec, Wait. Sarah Diesburg Operating Systems CS 3430
Week 2 Intro to the Shell with Fork, Exec, Wait Sarah Diesburg Operating Systems CS 3430 1 Why is the Shell Important? Shells provide us with a way to interact with the core system Executes programs on
More informationCreating a Shell or Command Interperter Program CSCI411 Lab
Creating a Shell or Command Interperter Program CSCI411 Lab Adapted from Linux Kernel Projects by Gary Nutt and Operating Systems by Tannenbaum Exercise Goal: You will learn how to write a LINUX shell
More informationFile Descriptors and Piping
File Descriptors and Piping CSC209: Software Tools and Systems Programming Furkan Alaca & Paul Vrbik University of Toronto Mississauga https://mcs.utm.utoronto.ca/~209/ Week 8 Today s topics File Descriptors
More informationRecitation 8: Tshlab + VM
Recitation 8: Tshlab + VM Instructor: TAs 1 Outline Labs Signals IO Virtual Memory 2 TshLab and MallocLab TshLab due Tuesday MallocLab is released immediately after Start early Do the checkpoint first,
More informationCS240: Programming in C
CS240: Programming in C Lecture 17: Processes, Pipes, and Signals Cristina Nita-Rotaru Lecture 17/ Fall 2013 1 Processes in UNIX UNIX identifies processes via a unique Process ID Each process also knows
More informationLayers in a UNIX System. Create a new process. Processes in UNIX. fildescriptors streams pipe(2) labinstructions
Process Management Operating Systems Spring 2005 Layers in a UNIX System interface Library interface System call interface Lab Assistant Magnus Johansson magnusj@it.uu.se room 1442 postbox 54 (4th floor,
More informationFloating-point lab deadline moved until Wednesday Today: characters, strings, scanf Characters, strings, scanf questions clicker questions
Announcements Thursday Extras: CS Commons on Thursdays @ 4:00 pm but none next week No office hours next week Monday or Tuesday Reflections: when to use if/switch statements for/while statements Floating-point
More information628 Lecture Notes Week 4
628 Lecture Notes Week 4 (February 3, 2016) 1/8 628 Lecture Notes Week 4 1 Topics I/O Redirection Notes on Lab 4 Introduction to Threads Review Memory spaces #include #include int
More informationComputer Systems Assignment 2: Fork and Threads Package
Autumn Term 2018 Distributed Computing Computer Systems Assignment 2: Fork and Threads Package Assigned on: October 5, 2018 Due by: October 12, 2018 1 Understanding fork() and exec() Creating new processes
More informationCS240: Programming in C
CS240: Programming in C Lecture 16: Process and Signals Cristina Nita-Rotaru Lecture 16/ Fall 2013 1 Processes in UNIX UNIX identifies processes via a unique Process ID Each process also knows its parent
More informationPipelines, Forks, and Shell
Scribe Notes for CS61: 11/14/13 By David Becerra and Arvind Narayanan Pipelines, Forks, and Shell Anecdote on Pipelines: Anecdote 1: In 1964, Bell Labs manager Doug Mcllroy sent a memo stating that programs
More informationFile Access. FILE * fopen(const char *name, const char * mode);
File Access, K&R 7.5 Dealing with named files is surprisingly similar to dealing with stdin and stdout. Start by declaring a "file pointer": FILE *fp; /* See Appendix B1.1, pg. 242 */ header
More informationOutline. OS Interface to Devices. System Input/Output. CSCI 4061 Introduction to Operating Systems. System I/O and Files. Instructor: Abhishek Chandra
Outline CSCI 6 Introduction to Operating Systems System I/O and Files File I/O operations File Descriptors and redirection Pipes and FIFOs Instructor: Abhishek Chandra 2 System Input/Output Hardware devices:
More informationOperating System Labs. Yuanbin Wu
Operating System Labs Yuanbin Wu cs@ecnu Annoucement Next Monday (28 Sept): We will have a lecture @ 4-302, 15:00-16:30 DON'T GO TO THE LABORATORY BUILDING! TA email update: ecnucchuang@163.com ecnucchuang@126.com
More informationContents. IPC (Inter-Process Communication) Representation of open files in kernel I/O redirection Anonymous Pipe Named Pipe (FIFO)
Pipes and FIFOs Prof. Jin-Soo Kim( jinsookim@skku.edu) TA JinHong Kim( jinhong.kim@csl.skku.edu) Computer Systems Laboratory Sungkyunkwan University http://csl.skku.edu Contents IPC (Inter-Process Communication)
More informationปฏ บ ต การ #3. A Simple Shell Interpreter
ปฏ ต การ #3 A Simple Shell Interpreter Write a shell (read section 1.3.3 and 1.4 in text book) that is similar to Figure 1-10 but contains enough code that it actually works so you can test it. You might
More informationInterprocess Communication E. Im
Interprocess Communication 2008 E. Im 1 Pipes (FIFO) Pipes are a way to allow processes to communicate with each other There are two kinds of pipes Unnamed pipes Named pipes Pipes are uni-directional They
More informationCS Operating system Fall Midterm I -- Oct 5, 2017 You have 75 min. Good Luck!
Name / ID (please PRINT) Seq#: Seat #: CS 3733.001 -- Operating system Fall 2017 -- Midterm I -- Oct 5, 2017 You have 75 min. Good Luck! This is a closed book/note examination. But You can use C reference
More informationUniversity of Ottawa School of Information Technology and Engineering
University of Ottawa School of Information Technology and Engineering Course: CSI3131 Operating Systems Professor: Miguel A. Garzón SEMESTER: Winter 2015 Date: Feb 26 2015 Hour: 14:30-16:00 (90 minutes)
More informationCS Operating Systems Lab 3: UNIX Processes
CS 346 - Operating Systems Lab 3: UNIX Processes Due: February 15 Purpose: In this lab you will become familiar with UNIX processes. In particular you will examine processes with the ps command and terminate
More informationCS 3113 Introduction to Operating Systems Midterm October 11, 2018
General instructions: CS 3113 Introduction to Operating Systems Midterm October 11, 2018 Please wait to open this exam booklet until you are told to do so. This examination booklet has 10 pages. You also
More informationCS 3113 Introduction to Operating Systems Midterm October 11, 2018
General instructions: CS 3113 Introduction to Operating Systems Midterm October 11, 2018 Please wait to open this exam booklet until you are told to do so. This examination booklet has 10 pages. You also
More informationCSE 410: Systems Programming
CSE 410: Systems Programming Input and Output Ethan Blanton Department of Computer Science and Engineering University at Buffalo I/O Kernel Services We have seen some text I/O using the C Standard Library.
More informationCSE 410: Systems Programming
CSE 410: Systems Programming Pipes and Redirection Ethan Blanton Department of Computer Science and Engineering University at Buffalo Interprocess Communication UNIX pipes are a form of interprocess communication
More informationCS Operating system Summer Midterm I -- July 11, 2017 You have 115 min (10:00am-11:55pm). Good Luck!
Name / ID (please PRINT) Seq#: Seat #: CS 3733.001 -- Operating system Summer 2017 -- Midterm I -- July 11, 2017 You have 115 min (10:00am-11:55pm). Good Luck! This is a closed book/note examination. But
More informationCS 25200: Systems Programming. Lecture 14: Files, Fork, and Pipes
CS 25200: Systems Programming Lecture 14: Files, Fork, and Pipes Dr. Jef Turkstra 2018 Dr. Jeffrey A. Turkstra 1 Lecture 14 File table and descriptors Fork and exec Fd manipulation Pipes 2018 Dr. Jeffrey
More informationCS167 Programming Assignment 1: Shell
CS167 Programming Assignment 1: Assignment Out: Sep. 5, 2007 Helpsession: Sep. 11, 2007 (8:00 pm, Motorola Room, CIT 165) Assignment Due: Sep. 17, 2007 (11:59 pm) 1 Introduction In this assignment you
More informationWorkshop on Inter Process Communication Solutions
Solutions 1 Background Threads can share information with each other quite easily (if they belong to the same process), since they share the same memory space. But processes have totally isolated memory
More informationLecture 7: file I/O, more Unix
CIS 330: / / / / (_) / / / / _/_/ / / / / / \/ / /_/ / `/ \/ / / / _/_// / / / / /_ / /_/ / / / / /> < / /_/ / / / / /_/ / / / /_/ / / / / / \ /_/ /_/_/_/ _ \,_/_/ /_/\,_/ \ /_/ \ //_/ /_/ Lecture 7: file
More informationProcess Management 1
Process Management 1 Goals of this Lecture Help you learn about: Creating new processes Programmatically redirecting stdin, stdout, and stderr (Appendix) communication between processes via pipes Why?
More informationOperating Systems Lab
Operating Systems Lab Islamic University Gaza Engineering Faculty Department of Computer Engineering Fall 2012 ECOM 4010: Operating Systems Lab Eng: Ahmed M. Ayash Lab # 3 Fork() in C and C++ programming
More informationComputer Science 330 Operating Systems Siena College Spring Lab 5: Unix Systems Programming Due: 4:00 PM, Wednesday, February 29, 2012
Computer Science 330 Operating Systems Siena College Spring 2012 Lab 5: Unix Systems Programming Due: 4:00 PM, Wednesday, February 29, 2012 Quote: UNIX system calls, reading about those can be about as
More informationC programming basics T3-1 -
C programming basics T3-1 - Outline 1. Introduction 2. Basic concepts 3. Functions 4. Data types 5. Control structures 6. Arrays and pointers 7. File management T3-2 - 3.1: Introduction T3-3 - Review of
More informationCSCI0330 Intro Computer Systems Doeppner. Project C-Shell. Due: October 31, 2018 at 11:59pm. 1 Introduction 2
CSCI0330 Intro Computer Systems Doeppner Project C-Shell Due: October 31, 2018 at 11:59pm 1 Introduction 2 2 Assignment 2 2.1 Makefile 3 2.2 Files, File Descriptors, Terminal I/O 5 2.3 Executing a Program
More informationMatt Ramsay CS 375 EXAM 2 Part 1
Matt Ramsay CS 375 EXAM 2 Part 1 Output: csserver:/home/mr56/cs375/exam2 > parent 1 75000 Multiples of 3 between 3 and 15000 add to 37507500 This total written to /home/mr56/tmp/file8771.out Multiples
More informationProcesses COMPSCI 386
Processes COMPSCI 386 Elements of a Process A process is a program in execution. Distinct processes may be created from the same program, but they are separate execution sequences. call stack heap STACK
More informationTopic 8: I/O. Reading: Chapter 7 in Kernighan & Ritchie more details in Appendix B (optional) even more details in GNU C Library manual (optional)
Topic 8: I/O Reading: Chapter 7 in Kernighan & Ritchie more details in Appendix B (optional) even more details in GNU C Library manual (optional) No C language primitives for I/O; all done via function
More informationPreview. Interprocess Communication with Pipe. Pipe from the Parent to the child Pipe from the child to the parent FIFO popen() with r Popen() with w
Preview Interprocess Communication with Pipe Pipe from the Parent to the child Pipe from the child to the parent FIFO popen() with r Popen() with w COCS 350 System Software, Fall 2015 1 Interprocess Communication
More informationCSC209H Lecture 3. Dan Zingaro. January 21, 2015
CSC209H Lecture 3 Dan Zingaro January 21, 2015 Streams (King 22.1) Stream: source of input or destination for output We access a stream through a file pointer (FILE *) Three streams are available without
More informationCS 33. Architecture and the OS. CS33 Intro to Computer Systems XIX 1 Copyright 2018 Thomas W. Doeppner. All rights reserved.
CS 33 Architecture and the OS CS33 Intro to Computer Systems XIX 1 Copyright 2018 Thomas W. Doeppner. All rights reserved. The Operating System My Program Mary s Program Bob s Program OS CS33 Intro to
More information2009 S2 COMP File Operations
2009 S2 COMP1921 9. File Operations Oliver Diessel odiessel@cse.unsw.edu.au Last updated: 16:00 22 Sep 2009 9. File Operations Topics to be covered: Streams Text file operations Binary file operations
More informationCS240: Programming in C
CS240: Programming in C Lecture 13 si 14: Unix interface for working with files. Cristina Nita-Rotaru Lecture 13/Fall 2013 1 Working with Files (I/O) File system: specifies how the information is organized
More informationCSci 4061 Introduction to Operating Systems. IPC: Basics, Pipes
CSci 4061 Introduction to Operating Systems IPC: Basics, Pipes Communication IPC in Unix Pipes: most basic form of IPC in Unix process-process ps u jon grep tcsh // what happens? Pipe has a read-end (receive)
More informationCSci 4061 Introduction to Operating Systems. IPC: Basics, Pipes
CSci 4061 Introduction to Operating Systems IPC: Basics, Pipes Communication IPC in Unix Pipes: most basic form of IPC in Unix process-process ps u jon grep tcsh // what happens? Pipe has a read-end (receive)
More informationDifferent network topologies
Network Topology Network topology is the arrangement of the various elements of a communication network. It is the topological structure of a network and may be depicted physically or logically. Physical
More informationSystem-Level I/O. Topics Unix I/O Robust reading and writing Reading file metadata Sharing files I/O redirection Standard I/O
System-Level I/O Topics Unix I/O Robust reading and writing Reading file metadata Sharing files I/O redirection Standard I/O A Typical Hardware System CPU chip register file ALU system bus memory bus bus
More informationForest Fire Simulation Using Multiple Processes and Pipes
CEG 434/634: Concurrent Software Design (Fall 2002) PROGRAMMING ASSIGNMENT I Forest Fire Simulation Using Multiple Processes and Pipes Distribution date: October 1 (Tuesday) Due Date: October 15 (Tuesday)
More informationPipes and FIFOs. Woo-Yeong Jeong Computer Systems Laboratory Sungkyunkwan University
Pipes and FIFOs Woo-Yeong Jeong (wooyeong@csl.skku.edu) Computer Systems Laboratory Sungkyunkwan University http://csl.skku.edu Open Files in Kernel How the Unix kernel represents open files? Two descriptors
More informationWindows architecture. user. mode. Env. subsystems. Executive. Device drivers Kernel. kernel. mode HAL. Hardware. Process B. Process C.
Structure Unix architecture users Functions of the System tools (shell, editors, compilers, ) standard library System call Standard library (printf, fork, ) OS kernel: processes, memory management, file
More informationCSC 1600 Unix Processes. Goals of This Lecture
CSC 1600 Unix Processes q Processes Goals of This Lecture q Process vs. program q Context switching q Creating a new process q fork: process creates a new child process q wait: parent waits for child process
More informationLecture 23: System-Level I/O
CSCI-UA.0201-001/2 Computer Systems Organization Lecture 23: System-Level I/O Mohamed Zahran (aka Z) mzahran@cs.nyu.edu http://www.mzahran.com Some slides adapted (and slightly modified) from: Clark Barrett
More informationCS 3733 Operating Systems
What will be covered in MidtermI? CS 3733 Operating Systems Instructor: Dr. Tongping Liu Department Computer Science The University of Texas at San Antonio Basics of C programming language Processes, program
More informationTHE C STANDARD LIBRARY & MAKING YOUR OWN LIBRARY. ISA 563: Fundamentals of Systems Programming
THE C STANDARD LIBRARY & MAKING YOUR OWN LIBRARY ISA 563: Fundamentals of Systems Programming Announcements Homework 2 posted Homework 1 due in two weeks Typo on HW1 (definition of Fib. Sequence incorrect)
More informationProcesses often need to communicate. CSCB09: Software Tools and Systems Programming. Solution: Pipes. Recall: I/O mechanisms in C
2017-03-06 Processes often need to communicate CSCB09: Software Tools and Systems Programming E.g. consider a shell pipeline: ps wc l ps needs to send its output to wc E.g. the different worker processes
More informationWhat Is Operating System? Operating Systems, System Calls, and Buffered I/O. Academic Computers in 1983 and Operating System
What Is Operating System? Operating Systems, System Calls, and Buffered I/O emacs gcc Browser DVD Player Operating System CS 217 1 Abstraction of hardware Virtualization Protection and security 2 Academic
More informationReading compiler errors
Reading compiler errors ls2.c:1: error: expected =,,, ;, asm or attribute before : token In file included from /usr/include/stdio.h:75, from ls2.c:12: /usr/include/libio.h:332: error: expected specifier-qualifier-list
More informationCSCI0330 Intro Computer Systems Doeppner. Project C-Shell. Due: November 1, 2017 at 11:59pm
CSCI0330 Intro Computer Systems Doeppner Project C-Shell Due: November 1, 2017 at 11:59pm IMPORTANT: The TAs will start grading Shell 1 the day after it is due. Therefore, if you ve handed in and might
More informationECE 435 Network Engineering Lecture 2
ECE 435 Network Engineering Lecture 2 Vince Weaver http://web.eece.maine.edu/~vweaver vincent.weaver@maine.edu 6 September 2018 Announcements Homework 1 will be posted. Will be on website, will announce
More informationCOP4342 UNIX Tools Assignment #3: A Simple Unix Shell. Instructor: Dr. Robert Van Engelen Teaching Assistant: Imran Chowdhury Spring 2018
Total Points: 100 COP4342 UNIX Tools Assignment #3: A Simple Unix Shell Instructor: Dr. Robert Van Engelen Teaching Assistant: Imran Chowdhury Spring 2018 Description: The bash shell utility on UNIX and
More informationContents. PA1 review and introduction to PA2. IPC (Inter-Process Communication) Exercise. I/O redirection Pipes FIFOs
Pipes and FIFOs Prof. Jin-Soo Kim( jinsookim@skku.edu) TA Dong-Yun Lee(dylee@csl.skku.edu) Computer Systems Laboratory Sungkyunkwan University http://csl.skku.edu Contents PA1 review and introduction to
More informationFiles and Directories
Files and Directories Administrative * HW# 1 Due this week Goals: Understand the file system concepts * files, links, and directories * device independent interface Topics: * 3.0 Device independence *
More informationThe course that gives CMU its Zip! I/O Nov 15, 2001
15-213 The course that gives CMU its Zip! I/O Nov 15, 2001 Topics Files Unix I/O Standard I/O A typical hardware system CPU chip register file ALU system bus memory bus bus interface I/O bridge main memory
More informationUNIVERSITY OF NEBRASKA AT OMAHA Computer Science 4500/8506 Operating Systems Fall Programming Assignment 1 (updated 9/16/2017)
UNIVERSITY OF NEBRASKA AT OMAHA Computer Science 4500/8506 Operating Systems Fall 2017 Programming Assignment 1 (updated 9/16/2017) Introduction The purpose of this programming assignment is to give you
More informationLAB 1: C PRIMER CS444/544 WENJIN HU JAN 16TH, 2009
LAB 1: C PRIMER CS444/544 WENJIN HU JAN 16TH, 2009 SIMPLE C PROGRAM helloworld.c #include int main() printf("hello world!"); return 0; csguest:~$ gcc helloworld.c -o helloworld Notice: what's
More informationA: We see the ps auxw execute and print on screen. The program holds the command in buffer then it is printed on screen.
Brian Duenas CSE 460 Lab 4 20 points Total 2. Process Pipes Q: What do you see when you execute "pipe1"? Why? We see the ps auxw execute and print on screen. The program holds the command in buffer then
More informationIntroduction to OS Processes in Unix, Linux, and Windows MOS 2.1 Mahmoud El-Gayyar
Introduction to OS Processes in Unix, Linux, and Windows MOS 2.1 Mahmoud El-Gayyar elgayyar@ci.suez.edu.eg Mahmoud El-Gayyar / Introduction to OS 1 Processes in Unix, Linux, and Windows Unix pre-empted
More informationContents. A Review of C language. Visual C Visual C++ 6.0
A Review of C language C++ Object Oriented Programming Pei-yih Ting NTOU CS Modified from www.cse.cuhk.edu.hk/~csc2520/tuto/csc2520_tuto01.ppt 1 2 3 4 5 6 7 8 9 10 Double click 11 12 Compile a single source
More informationCSC209 Fall Karen Reid 1
' & ) ) #$ "! How user programs interact with the Operating System. Somehow we need to convert a program into machine code (object code). A compiler passes over a whole program before translating it into
More informationCompile and execute fifo1.cpp listed above. Try the Balady's anomaly examples discussed in class. Did you observe the Belady's anomaly?
Tyler Gaynair Lab9 Score out of 20 Compile and execute fifo1.cpp listed above. Try the Balady's anomaly examples discussed in class. Did you observe the Belady's anomaly? Fifo.cpp code // fifo1.cpp: First
More informationUNIX System Programming. Overview. 1. A UNIX System. 2. Processes (review) 2.1. Context. Pipes/FIFOs
UNIX System Programming Pipes/FIFOs Overview 1. A UNIX System (review) 2. Processes (review) Objectives Look at UNIX support for interprocess communication (IPC) on a single machine Review processes pipes,
More informationCSI 402 Lecture 2 Working with Files (Text and Binary)
CSI 402 Lecture 2 Working with Files (Text and Binary) 1 / 30 AQuickReviewofStandardI/O Recall that #include allows use of printf and scanf functions Example: int i; scanf("%d", &i); printf("value
More informationFriday, September 16, Lab Notes. Command line arguments More pre-processor options Programs: Finish Program 1, begin Program 2 due next week
Friday, September 16, 2016 Lab Notes Topics for today Redirection of input and output Command line arguments More pre-processor options Programs: Finish Program 1, begin Program 2 due next week 1. Redirection
More informationContent. Input Output Devices File access Function of File I/O Redirection Command-line arguments
File I/O Content Input Output Devices File access Function of File I/O Redirection Command-line arguments UNIX and C language C is a general-purpose, high-level language that was originally developed by
More informationProcesses. Johan Montelius KTH
Processes Johan Montelius KTH 2017 1 / 47 A process What is a process?... a computation a program i.e. a sequence of operations a set of data structures a set of registers means to interact with other
More informationLecture 8: Structs & File I/O
....... \ \ \ / / / / \ \ \ \ / \ / \ \ \ V /,----' / ^ \ \.--..--. / ^ \ `--- ----` / ^ \. ` > < / /_\ \. ` / /_\ \ / /_\ \ `--' \ /. \ `----. / \ \ '--' '--' / \ / \ \ / \ / / \ \ (_ ) \ (_ ) / / \ \
More informationRicardo Rocha. Department of Computer Science Faculty of Sciences University of Porto
Ricardo Rocha Department of Computer Science Faculty of Sciences University of Porto For more information please consult Advanced Programming in the UNIX Environment, 3rd Edition, W. Richard Stevens and
More informationIntermediate Programming, Spring 2017*
600.120 Intermediate Programming, Spring 2017* Misha Kazhdan *Much of the code in these examples is not commented because it would otherwise not fit on the slides. This is bad coding practice in general
More informationProject 2: Shell with History1
Project 2: Shell with History1 See course webpage for due date. Submit deliverables to CourSys: https://courses.cs.sfu.ca/ Late penalty is 10% per calendar day (each 0 to 24 hour period past due). Maximum
More informationA process. the stack
A process Processes Johan Montelius What is a process?... a computation KTH 2017 a program i.e. a sequence of operations a set of data structures a set of registers means to interact with other processes
More informationChapter 1. Introduction
Chapter 1. Introduction System Programming http://www.cs.ccu.edu.tw/~pahsiung/courses/sp 熊博安國立中正大學資訊工程學系 pahsiung@cs.ccu.edu.tw Class: EA-104 (05)2720411 ext. 33119 Office: EA-512 Textbook: Advanced Programming
More informationNaked C Lecture 6. File Operations and System Calls
Naked C Lecture 6 File Operations and System Calls 20 August 2012 Libc and Linking Libc is the standard C library Provides most of the basic functionality that we've been using String functions, fork,
More informationUNIX input and output
UNIX input and output Disk files In UNIX a disk file is a finite sequence of bytes, usually stored on some nonvolatile medium. Disk files have names, which are called paths. We won t discuss file naming
More informationC BOOTCAMP DAY 2. CS3600, Northeastern University. Alan Mislove. Slides adapted from Anandha Gopalan s CS132 course at Univ.
C BOOTCAMP DAY 2 CS3600, Northeastern University Slides adapted from Anandha Gopalan s CS132 course at Univ. of Pittsburgh Pointers 2 Pointers Pointers are an address in memory Includes variable addresses,
More informationLinux Programming
Linux Programming CMPT 433 Slides #6 Dr. B. Fraser 18-05-22 1 Topics 1) How can we do multitasking? 2) How can our multiple tasks communicate? 3) How can we communicate over the network? 18-05-22 2 Concurrency:
More informationeverything is a file main.c a.out /dev/sda1 /dev/tty2 /proc/cpuinfo file descriptor int
everything is a file main.c a.out /dev/sda1 /dev/tty2 /proc/cpuinfo file descriptor int #include #include #include int open(const char *path, int flags); flagso_rdonly
More informationCS 550 Operating Systems Spring Process II
CS 550 Operating Systems Spring 2018 Process II 1 Recap: Process Informal definition: A process is a program in execution. Process is not the same as a program. Program is a passive entity stored in the
More informationOperating Systems. Review ENCE 360
Operating Systems Review ENCE 360 High level Concepts What are three conceptual pieces fundamental to operating systems? High level Concepts What are three conceptual pieces fundamental to operating systems?
More information