Critical section Problem Using Dekker's Algorithm

OBJECTIVE: Write a program for synchronizing of critical section problem using Dekker’s Algorithm.

THEORY: In concurrent programming a critical section is a piece of code that asses a shared resource (data structure or device ) that must not be concurrently accessed by more than one thread of execution. A critical section will usually terminate in fixed time, and a thread, task or process will only have to wait a fixed time to enter it (i.e. bounded waiting .

PROGRAM:

#include<sydio.h>

#include<conio.h>

void main()

{

int choice;

int c1=1,c2=1,turn=1;

clrscr();

do

{

printf(“\n1.Process 1 Enter”);

printf(“\n2.Process 2 Enter”);

printf(“\n3.Both Process Enter”);

printf(“\n4.Exit”);

scanf(“%d”,&choice);

if(choice==1)

{

c1=0;

while(c2==0)

{
                                if(turn==2)

c1=1

while(turn==2);

c1=0;

}

printf(“\nProcess P1 Enters the Critical section”);

c1=1;

turn=2;

else

printf(“\nIt is the turn process P2”);

}

if(choice==2)

{

                c2=0;

                while(c1==0)

{

                if(turn==1)

                c2=1;

while(turn==1);

c2=0;

}

printf(“\nProcess P2 enters in critical section”);

c2=1;

turn=1;

else

printf(“\nIt is turn of Process P1”);

}

}

while(choice!=4);

}

OUTPUT:

Enter  the choice:             1

Process 1 Enters Critical section

Enter choice       3

Both Process i