SAG315 - Network- Centric Programming - Mid-Term Exam - Solved

Problem 1 – Basic File Read/Write
 

Implement a program that can read from the keyboard and write to the file. First, create a file and write any sentence into the file. Then, read the sentence from the file and display it on the screen. You need to implement this problem with both systemcall and standard I/O functions. 

 

Make your code readable and robust and output standard Linux error messages if an error occurs. For example, if a file is failed to be opened (i.e., file descriptor <0), you can use perror("Opening File Failed") to output error messages.

 

You may need to include the following header files:

 

#include <sys/types.h>

#include <sys/uio.h>

#include <unistd.h>

#include <stdio.h>

#include <stdlib.h>

#include <fcntl.h>

#include <string.h>  

 

Problem 2 – Socket
 

Implement a basic socket server and client using the port 8080. After the connection is established, the client sends the following C string to the server.

"Network-Centric Programming – Spring 2021 Midterm"  

 

Once the server receives the message from the client, the server will print it out on the screen.

 

Make your code readable and robust and output standard Linux error messages if an error occurs. For example, if a socket is failed to be created, you can use perror("Socket Creation Failed") to output error messages.

 

You may need to include the following header files:

 

#include <stdio.h>

#include <sys/socket.h>

#include <stdlib.h>

#include <netinet/in.h>

#include <string.h>

#include <unistd.h>

#include <arpa/inet.h>

 

Problem 3 – Process
 

Implement a program that uses fork() to create a child process. In the parent process, please print out the C string "I’m in the parent process". And in the child process, please print out the string "I’m in the child process".

 

Make your code readable and robust and output standard Linux error messages if an error occurs. For example, if the child process is failed to be created, you can use perror("Process Creation Failed") to output error messages.

 

You may need to include the following header files:

 

#include <stdio.h>

#include <sys/types.h>

#include <unistd.h>

 

Problem 4 – Thread
 

Implement a program that uses pthread to create two threads. In the main thread and two created peer threads, please print out the following C strings, respectively.

 

"This is main thread.\n"

"This is the first created thread.\n"

"This is the second created thread.\n"

 

Make your code readable and robust and output standard Linux error messages if an error occurs. For example, if a thread is failed to be created, you can use perror("Thread Creation Failed") to output error messages.

 

You may need to include the following header files:

 

#include <pthread.h>

#include <stdio.h>

#include <unistd.h>

#include <stdlib.h>