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Remort Shell

The client program running on the client computer should connect to the server program running on the server computer. Then the client program should prompt for commands from the user, make them run on the server computer and print results back on the client computer's screen. This command-result sequence should run in a loop so that a number of commands can get run on the server. When the user enters the text "exit" on the client program the system should terminate. Implementation in C client.c /* compile Command : gcc -o client client.c                   ./client */ #include  <sys/types.h> #include  <sys/socket.h> #include  <sys/un.h> #include  <stdio.h> #include  <netinet/in.h> #include  <netdb.h> #include <stdlib.h> #define  PORT  1030    /* addr to connect */ #define  HOST  "localhost" ...
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Simple pipe implementation

#include <stdio.h> #include <unistd.h> #include <stdlib.h> int main(){     int pfds[2], status;     char *com1[]={"ls","-a",NULL};     char *com2[]={"sort",NULL};     switch(fork()){         case -1:              printf("Error has been occured");             exit(1);         case 0:             break;//Run the child         default:             wait(&status);//Parent is waiting until child exit             return (status);          }     if(pipe(pfds)<0)         exit(1);     s...
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Simple Boot Loader in Assembly

Terminal Commands: nasm boot1.asm -f bin -o boot1.bin dd if=boot1.bin bs=512 of=myhd.img qemu myhd.img Help for boot1.asm: 'INT 0x10' is a BIOS video interrupt. All video related calls are made through this interrupt. To use this interrupt, we need to set the values of some registers as follows.     AL => With ASCII value of character to display     AH => With 0x0E ;           Teletype mode (This will tell bios that we want to print one character on screen)     BL => With Text Attribute (This will be the fore ground and background color             of character to be displayed. 0x07 in our case.)     BH => With Page Number (0x00 for most of the cases)     Once all the registers are filled with appropriate values, we can call interrupt. Implementation in Assembly [BITS 16]    ...
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Posix Thread example

Get a file name from the command line to the main function and create that file. When SIGPWR is received, each thread should write the following line to the created file. The sum from ``low'' to ``i'' is ``myresult''. Also in the main function, before the threads are created, print the process id of the parent process so that you can send SIGPWR to it using the ``kill'' function from another terminal. Implementation in C #include <stdio.h> #include <pthread.h> #include <signal.h> #include <unistd.h> #include <stdlib.h> #include <string.h> #define ARRAYSIZE 1000 #define THREADS 10 #define TRUE 1 #define FALSE 0 void *slave(void *myid); void pwrhandler(int signal); //Signal handling function for PWR signal /* shared data */ int data[ARRAYSIZE]; /* Array of numbers to sum */ int sum = 0; pthread_mutex_t mutex; /* mutually exclusive lock variable */ int wsize;          /* size o...
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