Cs9227 - Operating System Lab Manual

CS9227

OPERATING SYSTEM LAB

MULTIPROCESSOR OPERATING SYSTEMS

PROGRAM 1 – Semaphores - Multiprocessor operating systems

Assume there are three processes: Pa, Pb, and Pc. Only Pa can output the letter A,

Pb B, and Pc C. Utilizing only semaphores (and no other variables) the processes

are synchronized so that the output satisfies the following conditions:

a) A B must be output before any C's can be output.

b) B's and C's must alternate in the output string, that is, after the first B is output,

another B cannot be output until a C is output. Similarly, once a C is output,

another C cannot be output until a B is output.

c) The total number of B's and C's which have been output at any given point in the

output string cannot exceed the number of A's which have been output up to that

point.

Examples

AACB -- invalid, violates a)

ABACAC -- invalid, violates b)

AABCABC -- invalid, violates c)

AABCAAABC -- valid

AAAABCBC -- valid

AB -- valid

TOTAL : 45 PERIODS

MULTIPROCESSOR OPERATING SYSTEM(ABCs)

AIM:

To write a java program for multiprocessor operating system using

semaphores.

ALGORITHM:

Step 1: Start the program.

Step 2: Declare the variables for more than two processes.

Step 3: Declare the entry section for P1 and entry section for P2.

Step 4: Define Q1:=TRUE and Q2:=TRUE.

Step 5: Assign TURN:=1 and TURN:=2.

Step 6: Wait while Q2 of TURN:=1 and wait while Q1 of TURN:=2.

Step 7: The processes are synchronized, so that output displayed in the order ABC.

Step 8: Exit from section for P1 and exit section for P2 while Q1!=FALSE and

Q2:=FALSE.

Step 9: B’s and C’s must be alternate in the output String i.e) after the first B is

displayed, another B cannot be the displayed until a C is displayed.

Step 10: Similarly, once C is displayed, another C cannot be displayed until a B is

displayed.

Step 11: The total number of B’s and C’s which have been displayed at any given

point in the output string cannot exceed.

Step 12: Utilize only semaphores, the processes are synchronized so that the output

is satisfied.

Step 13: Execute the program.

PROGRAM:

ABCs.java

import java.io.Serializable;

import java.util.Date;

import java.util.Random;

class BinarySemaphore

{

private boolean locked = false;

BinarySemaphore() {} // constructors

BinarySemaphore(boolean initial)

{

locked = initial;

}

BinarySemaphore(int initial)

{

locked = (initial == 0);

}

public synchronized void P()

{

while (locked)

{

try

{

wait();

}

catch (InterruptedException e)

{ }

}

locked = true;

}

public synchronized void V()

{

if (locked) notify();

locked = false;

}

}

class CountingSemaphore

{

private int value = 0;

private int waitCount = 0;

private int notifyCount = 0;

public CountingSemaphore(int initial)

{

if (initial > 0) value = initial;

}

public synchronized void P()

{

if (value <= waitCount)

{

waitCount++;

try

{

do

{

wait();

} while (notifyCount == 0);

}

catch(InterruptedException e)

{

notify();

}

finally

{

waitCount--;

}

notifyCount--;

}

value--;

}

public synchronized void V()

{

value++;

if (waitCount > notifyCount)

{

notifyCount++;

notify();

}

}

}

class Pa extends ABCs implements Runnable

{ // extend ABCs to

// access semaphore sum

public void run ()

{

while (true)

{

nap(1+(int)(random(500)));

System.out.print("A"); System.out.flush();

try

{

V(sum);

}

catch (Exception e){}

}

}

}

class Pb extends ABCs implements Runnable

{

public void run ()

{

while (true)

{


P(C); P(sum);

System.out.print("B"); System.out.flush();

V(B);

}

}

}

class Pc extends ABCs implements Runnable

{

public void run ()

{

while (true)

{


P(B); P(sum);

System.out.print("C"); System.out.flush();

V(C);

}

}

}

class ABCs

{

protected static final BinarySemaphore B // these semaphores

= new BinarySemaphore(0); // are static

protected static final BinarySemaphore C // so subclasses

= new BinarySemaphore(1); // Pa, Pb,

protected static final CountingSemaphore sum // and Pc share

= new CountingSemaphore(0); // them

private static final long startTime = System.currentTimeMillis();

protected static final long age()

{

return System.currentTimeMillis() - startTime;

}

private static final Random rnd = new Random();

protected static final double random()

{

return rnd.nextDouble();

}

protected static final double random(int ub)

{

return rnd.nextDouble()*ub;

}

protected static final void P(BinarySemaphore s)

{

s.P();

}

protected static final void V(BinarySemaphore s)

{

s.V();

}

protected static final void P(CountingSemaphore s)

{

s.P();

}

protected static final void V(CountingSemaphore s)

{

s.V();

}

protected static final int nap(int napTimeMS)

{

long napStart = age();

try

{

Thread.sleep(napTimeMS);

}

catch (InterruptedException e)

{

System.err.println("interrupted out of sleep");

}

return (int) (age() - napStart - (long) napTimeMS);

}

public static void main(String[] args) throws InterruptedException

{

Thread pa = new Thread(new Pa());

Thread pb = new Thread(new Pb());

Thread pc = new Thread(new Pc());

pa.start(); pb.start(); pc.start();

nap(9000);

pa.stop(); pb.stop(); pc.stop();

System.exit(0);

}

}

OUTPUT:

D:\Java\jdk1.6.0\bin>javac ABCs.java

D:\Java\jdk1.6.0\bin>java ABCs

ABACABACABACAAABCABACBACABACABACABACABACABACABACAAAABC

AAABCABCAA

RESULT:

Thus the java program for multiprocessor operating system using

semaphores is written and the output is executed successfully.

PROGRAM 2 – Multithreading - Multiprocessor operating systems

The Cigarette Smokers Problem

Consider a simulation with three smoker threads and one agent thread. Each

smoker continuously makes a cigarette and smokes it. But to make a cigarette, a

smoker needs three ingredients: tobacco, paper, and matches. One of the smoker

threads has only paper, another has only tobacco, and the third has only matches.

The agent thread has an infinite supply of all three materials. The three smoker

threads are initially blocked. The agent places two randomly chosen (different)

ingredients on the table and unblocks the one smoker who has the remaining

ingredient. The agent then blocks. The unblocked smoker removes the two

ingredients from the table, makes a cigarette, and smokes it for a random amount of

time, unblocking the agent on completion of smoking the cigarette. The agent then

puts out another random two of the three ingredients, and the cycle repeats.

Write a multi-class multithreaded Java program that uses a monitor to

synchronize the agent thread and the three smoker threads. Do not mechanically

translate semaphore code into monitor code! The agent thread executes in an

agent object created from an agent class. Each smoker thread executes in a smoker

object. All smoker objects are created from one smoker class whose constructor is

used to specify the ingredient possessed by the smoker object. A driver class with a

main method constructs the objects and starts the threads. Use a single monitor

object instantiated from a class Control for synchronization. Each of the four

threads invokes a synchronized monitor method for its synchronization. No

semaphores are allowed. No synchronized blocks are allowed, only synchronized

methods. No busy waiting is allowed. No calls to nap inside a synchronized method

are allowed (do not nap while holding the monitor object's lock, that is, while inside

a synchronized method or while inside a method called by a synchronized method).

CIGRETTE SMOKERS PROBLEM

AIM:

To Write a Java program for multiclass multithread that uses a monitor to

synchronize the agents thread and three smokers thread.

ALGORITHM:

Step 1: Start the Program.

Step 2: Declare the variables to define agent and smoker and its needs.

Step 3: do forever {

P(lock);

randNum=rand(1,3); }

Step 4: if (randNum==1) {

V(smoker-match);

}

Step 5: Else if(randNum==2) {

V(smoker-paper);

}

Step 6: Else {

V(smoker-tobacco);

V(lock);

P(agent); }

Step 7: In smokers code and other analgus do forever{

P(smoker-tobacco);

P(lock);

V(agent);

V(lock); }

Step 8: Use a single monitor object instantiated from a class control for

synchronization. No smokers, semaphores, synchronized blocks are allowed, allows

only Synchronized methods.

Step 9: No smokers semaphores, synchronized blocks are allowed allows only

synchronized methods.

Step 10: No class to map inside a synchronized methods are allowed.

Step 11: Each smoker thread has only thing to include inhale cigarette.

Step 12: But three smokers threads are initially blocked. The agent places two

randomly chosen ingredients on the table and unblocks the smoker who has

remaining ingredients agents then block

Do forever {

P(lock);

randNum=rand(1,3);

if(randNum==1)

{

V(smoker_match);

} }

Step 13: Execute the Program.

PROGRAM:

Agent.java

import java.util.*;

public class Agent extends Thread

{

private Table table;

private Random rand;

public Agent(Table tab,String name)

{

super(name);

table=tab;

rand=new Random();

}

public void run()

{

while(true)

{

switch(Math.abs(rand.nextInt())%3)

{

case 0: table.put(Table.Tobacco_Paper);

break;

case 1: table.put(Table.Paper_Matches);

break;

case 2: table.put(Table.Matches_Tobacco);

break;

}

}

}

}

Smoker .java

import java.util.*;

public class Smoker extends Thread

{

private Table table;

private Random rand;

private int needs;

public Smoker(Table tab,String name,int what)

{

super(name);

table=tab;

rand=new Random();

needs=Table.Everything^what;

}

public void run()

{

while(true)

{

try

{

table.get(needs);

System.out.println(getName()+":Rolling.");

sleep(Math.abs(rand.nextInt())%1000);

System.out.println(getName()+":Smoking.");

sleep(Math.abs(rand.nextInt())%1000);

System.out.println(getName()+":Done Smoking.");

table.DoneSmoking();

}

catch(InterruptedException e){}

}

}

}

Table.java

import java.util.*;

public class Table

{

public static final int Nothing=0;

public static final int Tobacco=1;

public static final int Paper=2;

public static final int Matches=4;

public static final int Tobacco_Paper=Tobacco+Paper;

public static final int Paper_Matches=Paper+Matches;

public static final int Matches_Tobacco=Matches+Tobacco;

public static final int Everything=Tobacco+Paper+Matches;

private int contains;

public Table()

{

contains=Nothing;

}

public synchronized void put(int what)

{

System.out.println(Thread.currentThread().getName()+":putting"+contains(what));

contains=contains|what;

notifyAll();

try{

wait();

}


}

public synchronized void get(int what)

{

while((contains&what)!=what)

{

try

{

System.out.println(Thread.currentThread().getName()+":getting"+contains

(what)+"-No!");

wait();

}


}

System.out.println(Thread.currentThread().getName()+":getting"+contains

(what)+"-Yes!");

contains=contains^what;

}

public synchronized void DoneSmoking()

{

notifyAll();

}

public String contains(int what)

{

String s="";

if((what&Tobacco)==Tobacco)

s=s+"tobacco";

if((what&Paper)==Paper)

s=s+"paper";

if((what&Matches)==Matches)

s=s+"matches";

return s;

}

}

TableCS.java

import java.util.*;

public class TableCS extends Table

{

TableCS Table;

}

cigarette.java

import java.util.*;

public class cigarette

{

public static void main(String[] args)

{

Smoker smo1,smo2,smo3;

Agent agent;

Table table;

table=new Table();

agent=new Agent(table,"Agent");

smo1=new Smoker(table,"Smoker 1",Table.Paper);

smo2=new Smoker(table,"Smoker 2",Table.Matches);

smo3=new Smoker(table,"Smoker 3",Table.Tobacco);

agent.start();

smo1.start();

smo2.start();

smo3.start();

}

}

OUTPUT:

D:\Java\jdk1.6.0\bin>javac Cigrate.java

D:\Java\jdk1.6.0\bin>java Cigrate

Agent:Puttingtobaccopaper

Smoker2:Gettingpapermatches-No!

Smoker1:Gettingtobaccomatches-No!

Smoker3:I Got What I Need!!!

Smoker3:Rolling!!

Smoker3:Smoking!!

Smoker3:Done Smoking!!


Smoker1:Gettingtobaccomatches-Yes!

Smoker3:Rolling!!


Smoker2:Gettingpapermatches-Yes!


Agent:Puttingtobaccomatches





Smoker3:Smoking!!


Smoker3:Gettingtobaccopaper-No!





Agent:Puttingtobaccopaper





Smoker3:Gettingtobaccopaper-Yes!


Smoker3:Rolling!!

Smoker3:Smoking!!







Agent:Puttingpapermatches

Smoker3:Gettingtobaccopaper-Yes!






RESULT:

Thus the java program for multi-class Multithreading- multiprocessor that

uses a monitor to synchronize the agent, thread and the three smoker threads are

written and the output is executed successfully.

PROGRAM 3 – Multiple sleeping barbers - Multiprocessor operating

systems

Write a multi-class multithreaded Java program that simulates multiple

sleeping barbers, all in one barbershop that has a finite number of chairs in the

waiting room. Each customer is instantiated from a single Customer class, each

barber is instantiated from a single Barber class.

SLEEPING BARBERS PROBLEM

AIM:

To write a multiclass multithread java program that simulates multiple

sleeping barbers.

ALGORITHM:

Step1: The Barber (Thread/Process)

while(true)

{ run in an infinite loop

P(customers)//tries to acquire a customer if name is

available,he goes to sleep

Step 2: P(access state) at this time he has been awakened, want to modify the

number of available seats.

Step 3: Number of free state++//one gets free.

Step 4: V(Barber)//the barber is ready to cut.

V(access seats)//we don’t need the lock on the chairs anyone,the barber

is cutting hair.

Step 5: The customer (Thread/process)

While (true) { //run in infinite loop

P(access seats) //tries to get access the chairs

Step 6: If the number of free seats is greater than 0, are any customers sitting down

on a chair, notify the barber who is waiting that there is a customer.

Step 7: V(access seats) don’t need to lock the chairs anyone, now its this customers

turn, but wait if wait the barber if busy, here the customer is having his hair cut.

Step 8: Else there are no free seats Lock(V)(access seats) but release the lock or the

seats, customers leaves without a haircut.

Step 9: Stop the program.

PROGRAM:

SleepingBarber.java

class Semaphore extends Object

{

private int count;

public Semaphore(int startingCount)

{

count=startingCount;

}

public void down()

{

synchronized(this)

{

while(count<=0)

{

try

{

wait();

}

catch(InterruptedException ex)

{ }

}

count--;

}

}

public void up()

{

synchronized(this)

{

count++;

if(count==1)

{

notify();

}

}

}

}

public class SleepingBarber extends Thread

{

public static Semaphore customers=new Semaphore(0);

public static Semaphore barbers=new Semaphore(0);

public static Semaphore mutex=new Semaphore(1);

public static int waiting=0;

public static final int CHAIRS=5;

class Barber extends Thread

{

private int myNumber;

public Barber(int i)

{

myNumber=i;

}

public void run()

{

while(true)

{

customers.down();

mutex.down();

waiting=waiting-1;

barbers.up();

mutex.up();

cut_hair();

}

}

public void cut_hair()

{

System.out.println("Barber"+myNumber+"is cutting hair");

try

{

sleep(7500);

}


{ }

}

}

private class Customer extends Thread

{


public Customer(int i)

{

myNumber=i;

}

public void run()

{

mutex.down();

if(waiting<CHAIRS)

{

waiting=waiting+1;

customers.up();

mutex.up();

barbers.down();

get_haircut();

}

else

{

mutex.up();

}

}

public void get_haircut()

{

System.out.println("Customers"+myNumber+"is getting his

haircut");

try

{

sleep(10000);

}


{ }

}

}

public static void main(String args[])

{

SleepingBarber holder=new SleepingBarber();

holder.start();

}

public void run()

{

final int BARBERS=3;

Barber aBarber;

Customer aCustomer;

for(int i=0;i<BARBERS;i++)

{

aBarber=new Barber(i);

aBarber.start();

}

int customerNumber=0;

while(true)

{

aCustomer=new Customer(customerNumber++);

aCustomer.start();

try

{

sleep(1000);

}

catch(InterruptedException ex){};

}

}

}

SleepingBarberD.java

class Semaphore extends Object

{

private int count;

public Semaphore(int startingCount)

{

count=startingCount;

}

public void down()

{

synchronized(this)

{

while(count<=0)

{

try

{

wait();

}


{}

}

count--;

}

}

public void up()

{

synchronized(this)

{

count++;

if(count==1)

{

notify();

}

}

}

}

public class SleepingBarberD extends Thread

{

public static Semaphore customers=new Semaphore(0);

public static Semaphore barbers=new Semaphore(0);

public static Semaphore mutex=new Semaphore(1);

public static int waiting=0;

public static final int CHAIRS=5;

class Barber extends Thread

{


public Barber(int i)

{

myNumber=i;

}

public void run()

{

while(true)

{

customers.down();

mutex.down();

waiting=waiting-1;

barbers.up();

mutex.up();

cut_hair();

}

}

public void cut_hair()

{

System.out.println("Barber"+myNumber+"is cutting hair");

try

{

sleep(7500);

}


{}

}

}

private class Customer extends Thread

{


public Customer(int i)

{

myNumber=i;

}

public void run()

{

mutex.down();

if(waiting<CHAIRS)

{

waiting=waiting+1;

customers.up();

mutex.up();

try

{

sleep(1000);

}


{}

try

{

sleep(1000);

}


{}

try

{

sleep(1000);

}


{}

barbers.down();

get_haircut();

}

else

{

mutex.up();

}

}

public void get_haircut()

{

System.out.println("Customers"+myNumber+"is getting his

haircut");

try

{

sleep(10000);

}


{}

}

}

public static void main(String args[])

{

SleepingBarberD holder=new SleepingBarberD();

holder.start();

}

public void run()

{

final int BARBERS=3;

Barber aBarber;

Customer aCustomer;

for(int i=0;i<BARBERS;i++)

{

aBarber=new Barber(i);

aBarber.start();

}

int customerNumber=0;

while(true)

{

aCustomer=new Customer(customerNumber++);

aCustomer.start();

try

{

sleep(1000);

}

catch(InterruptedException ex){}

}

}

}

OUTPUT:

D:\Java\jdk1.6.0\bin> javac SleepingBarber.java

D:\Java\jdk1.6.0\bin> java SleepingBarber

Barber0is cutting hair

Customers0is getting his haircut



































RESULT:

Thus the java program that simulates multiclass multithread - multiple

sleeping barbers using semaphores is written and the output is executed

successfully

NETWORK OPERATING SYSTEMS

PROGRAM 4 – Network operating systems

Establish a Lab setup for the following network operating systems based programs

based on the skills in networking on your own. E.g. for identifying networking

hardware, identifying different kinds of network cabling and network interface

cards can be done.

Exercises

1. Identifying Local Area Network Hardware

2. Exploring Local Area Network Configuration Options

3. Verifying TCP/IP Settings

4. Sharing Resources

5. Testing LAN Connections

NETWORK OPERATING SYSTEM

Aim:

To write a program for activating LAN connections between two systems.

Algorithm:


Step 2: Declare the IP address and MAC address to open a connection between

corresponding systems.

Step 3: Type ipconfig/all in command prompt, we get the IP address and MAC

address of own system.

Step 4: Type the MAC address as different formats.

Step 5: Type the source code.

Step 6: Compile the program and execute.

Step 7: Run the program by declaring IP address and MAC address of destination.

PROGRAM:

WakeOnLan.java

import java.io.*;

import java.net.*;

public class WakeOnLan

{

public static final int PORT=9;

public static void main(String[ ] args)

{

if(args.length!=2)

{

System.out.println("usuage:javaWakeOnLan1<broadcast-ip>

<mac-address>");

System.out.println ("Example:java WakeOnLan1 172.15.169.7

00-15-58-AC-0C-20");

System.out.println ("Example:java WakeOnLan1 172.15.169.8

00-15-58-AC-0C-27");

System.exit(1);

}

String ipStr=args[0];

String macStr=args[1];

try

{

byte[ ] macBytes=getMacBytes(macStr);

byte[] bytes=new byte[6+16*macBytes.length];

for(int i=0;i<6;i++)

{

bytes[i]=(byte)0xff;

}

for(int i=6;i<bytes.length;i+=macBytes.length)

{

System.arraycopy(macBytes, 0,bytes,i,macBytes.length);

}

InetAddress address = InetAddress.getByName(ipStr);

DatagramPacketpacket =

newDatagramPacket(bytes,bytes.length,

address,

PORT);

DatagramSocket socket= new DatagramSocket();

socket.send(packet);

socket.close();

System.out.println("wake on lan packet sent");

}

catch(Exception e)

{

System.out.println("failed to send wake on lan packet:+e");

System.exit(1);

}

}

private static byte[] getMacBytes(String macStr) throws

IllegalArgumentException

{

byte[] bytes=new byte[6];

String[] hex=macStr.split("(\\:|\\-)");

if(hex.length!=6)

{

throw new IllegalArgumentException("Invalid MAC address");

}

try

{

for(int i=0;i<6;i++)

{

bytes[i]=(byte)Integer.parseInt(hex[i],16);

}

}

catch(NumberFormatException e)

{

throw new IllegalArgumentException("invalid hex digit in MAC

address");

}

return bytes;

}

}

OUTPUT:

D:\Java\jdk1.6.0\bin>javac WakeOnLan.java

D:\Java\jdk1.6.0\bin>java WakeOnLan 172.15.169.7 00-15-58-AC-0C-20

Wake on LAN packet sent

RESULT:

Thus the program for activating LAN connections between two systems is written and the output is executed successfully.

REAL TIME OPERATING SYSTEMS

PROGRAM 5 – Real time operating systems

A real-time program implementing an alarm clock shall be developed. [Alarm

clock, using C and Simple_OS]

The program shall fulfill the following requirements:

Clock with alarm functionality shall be implemented, It shall be possible to

set the time, It shall be possible to set the alarm time, the alarm shall be enabled

when the alarm time is set, the alarm shall be activated when the alarm is enabled,

and when the current time is equal to the alarm time, an activated alarm must be

acknowledged. Acknowledgement of an alarm shall lead to the alarm being

disabled, the alarm is enabled again when a new alarm time is set, an alarm which

is not acknowledged shall be repeated every 10 seconds. The program shall

communicate with a graphical user interface, where the current time shall be

displayed, and where the alarm time shall be displayed when the alarm is enabled.

It shall be possible to terminate the program, using a command which is sent from

the graphical user interface.

REAL TIME OS

AIM:

To write a program using Real time operating system for implementing an alarm

clock.

ALGORITHM:


Step 2: Display init is used for initialization and shall be called from the main

function of the program before the processes are created.

Step 3: Display alarm time a shows the current time and shall be called when a new

alarm time is set.

Step 4: Display time is used to display the current time and shall be called by the

clock process.

Step 5: Erase the alarm time, erases the displayed alarm time and shall be called

when the user acknowledges an alarm.

Step 6: Display alarm text is used to show an alarm activation and the user is

informed that the alarm has been activated.

Step 7: when the alarm is activated the first time and when the alarm is activated

repeatedly.

Step 8: Erase alarm text,erase the information displayed by displays the alarm text.

Step 9: Stop the program.

PROGRAM:

Alarm.c

#include<stdio.h>

#include<conio.h>

#include<dos.h>

struct clk

{

int hh,mm,ss;

}c1,c2;

void clock(int *h1,int *m1,int *s1)

{

*s1=*s1+1;

if(*s1==60)

{

*s1=0; *m1=*m1+1;

if(*m1==60)

{

*m1=0;*h1=*h1+1;

if(*h1==24)

*h1=0;

}

}

}

void timer(int *h,int *m,int *s)

{

if((*s)!=0)

{

*s=*s-1;

}

else if((*s)==0)

{

if(*m!=0)

{

*s=59;*m=*m-1;

}

else if(*m==0)

{

if(*h!=0)

{

*m=59;*h=*h-1;

}

}

}

}

void alarm()

{

int i;

while(!kbhit())

{

for(i=0;i<2;i++)

{

sound(5000);

delay(100);

nosound();

delay(200);

}

delay(500);

}

}

void main()

{

char ch;

struct time t;

clrscr();

printf("\nPress:-\n\tA: for alarm Clock\n\tT: for Timer\n");

printf("\Enter your Choice:");

ch=getche();

switch (ch)

{

case 'A':

case 'a':

{

printf("\n\n\n24 hr Format(HH:MM:SS)");

gettime(&t);

c1.hh=t.ti_hour; c1.mm=t.ti_min; c1.ss=t.ti_sec;

printf("\nEnter alarm time : ");

scanf("%d:%d:%d",&c2.hh,&c2.mm,&c2.ss);

if(c2.hh>24||c2.mm>60||c2.ss>60)

{

printf("\n\n\tERROR: Invalid time.\n\tRestart the program.");

delay(2500);exit(0);

}

while((c1.ss!=c2.ss)||(c1.hh!=c2.hh)||(c1.mm!=c2.mm))

{

clrscr();

printf("\n\nAlarm time:

%02d:%02d:%02d\n",c2.hh,c2.mm,c2.ss);

printf("\nCurrent Time:

%02d:%02d:%02d",c1.hh,c1.mm,c1.ss);

clock(&c1.hh,&c1.mm,&c1.ss);

delay(1000);

};

clrscr();

printf("\n\n\n\n\t\t\t\tAlarm time me reached

\n\n\t\t\t\tPress any to Exit.");

alarm();

exit(0);

}

break;

case 'T':

case 't':

{

printf("\n\n\nEnter time for timer (HH:MM:SS): ");

scanf("%d:%d:%d",&c1.hh,&c1.mm,&c1.ss);

while(c1.hh>0||c1.mm>0||c1.ss>0)

{

clrscr();

printf("The Current Time:\n");

printf("\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\t\t\t\t");

printf("%02d:%02d:%02d",c1.hh,c1.mm,c1.ss);

timer(&c1.hh,&c1.mm,&c1.ss);

delay(1000);

}

clrscr();

printf("Program Written by: Anshu Krishna\n");

printf("\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\t\t\t\t");

printf("00:00:00");

alarm();

exit(0);

}

break;

default:

{

printf("\n\tInvalid Input\n\n\tPlease restart the program");

delay(2500);exit(0);

}

}

}

OUTPUT:

Press:-

A: for alarm Clock

T: for Timer

Enter your Choice:A

24 hr Format(HH:MM:SS)

Enter alarm time : 22:30:50

Alarm time: 22:20:50

Current Time: 22:19:53

Alarm time reached

Press any to Exit.

Press:-

A: for alarm Clock

T: for Timer

Enter your Choice: T

Enter time for timer (HH:MM:SS): 22:25:20

The Current Time:

22:25:06

Press:-

A: for alarm Clock

T: for Timer

Enter your Choice:2

Invalid Input

Please restart the program

RESULT:

Thus the program using Real time operating system for implementing an

alarm clock.is written and the output is executed successfully.

Documents

Cs9227 - Operating System Lab Manual