os lab extended

Tuesday 12 May 2015

Program 12a):

AIM: To implement page replacement algorithms FIFO (First In First Out)

#include<stdio.h>

#include<conio.h>

int i,j,nof,nor,flag=0,ref[50],frm[50],pf=0,victim=-1;

void main()

{

clrscr();

printf("\n \t\t\t FIFI PAGE REPLACEMENT ALGORITHM");

printf("\n Enter no.of frames....");

scanf("%d",&nof);

printf("Enter number of reference string..\n");

scanf("%d",&nor);

printf("\n Enter the reference string..");

for(i=0;i<nor;i++)

scanf("%d",&ref[i]);

printf("\nThe given reference string:");

for(i=0;i<nor;i++)

printf("%4d",ref[i]);

for(i=1;i<=nof;i++)

frm[i]=-1;

printf("\n");

for(i=0;i<nor;i++)

{

flag=0;

printf("\n\t Reference np%d->\t",ref[i]);

for(j=0;j<nof;j++)

{

if(frm[j]==ref[i])

{

flag=1;

break;

}}

if(flag==0)

{

pf++;

victim++;

victim=victim%nof;

frm[victim]=ref[i];

for(j=0;j<nof;j++)

printf("%4d",frm[j]);

}

printf("\n\n\t\t No.of pages faults...%d",pf);

getch();

}

OUTPUT:

Program 12b):

AIM: To implement page replacement algorithm LRU (Least Recently Used)

#include<stdio.h>

#include<conio.h>

int i,j,nof,nor,flag=0,ref[50],frm[50],pf=0,victim=-1;

int recent[10],lrucal[50],count=0;

int lruvictim();

void main()

{

clrscr();

printf("\n\t\t\t LRU PAGE REPLACEMENT ALGORITHM");

printf("\n Enter no.of Frames....");

scanf("%d",&nof);

printf(" Enter no.of reference string..");

scanf("%d",&nor);

printf("\n Enter reference string..");

for(i=0;i<nor;i++)

scanf("%d",&ref[i]);

printf("\n\n\t\t LRU PAGE REPLACEMENT ALGORITHM ");

printf("\n\t The given reference string:");

printf("\n………………………………..");

for(i=0;i<nor;i++)

printf("%4d",ref[i]);

for(i=1;i<=nof;i++)

{

frm[i]=-1;

lrucal[i]=0;

}

for(i=0;i<10;i++)

recent[i]=0;

printf("\n");

for(i=0;i<nor;i++)

{

flag=0;

printf("\n\t Reference NO %d->\t",ref[i]);

for(j=0;j<nof;j++)

{

if(frm[j]==ref[i])

{

flag=1;

break;

}

if(flag==0)

{

count++;

if(count<=nof)

victim++;

else

victim=lruvictim();

pf++;

frm[victim]=ref[i];

for(j=0;j<nof;j++)

printf("%4d",frm[j]);

}

recent[ref[i]]=i;

}

printf("\n\n\t No.of page faults...%d",pf);

getch();

}

int lruvictim()

{

int i,j,temp1,temp2;

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

{

temp1=frm[i];

lrucal[i]=recent[temp1];

}

temp2=lrucal[0];

for(j=1;j<nof;j++)

{

if(temp2>lrucal[j])

temp2=lrucal[j];

}

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

if(ref[temp2]==frm[i])

return i;

return 0;

}

OUTPUT:

Program 12c):

AIM: To implement page replacement algorithms Optimal (The page which is not used for longest time)

#include<stdio.h>

#include<conio.h>

int i,j,nof,nor,flag=0,ref[50],frm[50],pf=0,victim=-1;

int recent[10],optcal[50],count=0;

int optvictim();

void main()

{

clrscr();

printf("\n OPTIMAL PAGE REPLACEMENT ALGORITHN");

printf("\n.................................");

printf("\nEnter the no.of frames");

scanf("%d",&nof);

printf("Enter the no.of reference string");

scanf("%d",&nor);

printf("Enter the reference string");

for(i=0;i<nor;i++)

scanf("%d",&ref[i]);

clrscr();

printf("\n OPTIMAL PAGE REPLACEMENT ALGORITHM");

printf("\n................................");

printf("\nThe given string");

printf("\n....................\n");

for(i=0;i<nor;i++)

printf("%4d",ref[i]);

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

{

frm[i]=-1;

optcal[i]=0;

}

for(i=0;i<10;i++)

recent[i]=0;

printf("\n");

for(i=0;i<nor;i++)

{

flag=0;

printf("\n\tref no %d ->\t",ref[i]);

for(j=0;j<nof;j++)

{

if(frm[j]==ref[i])

{

flag=1;

break;

}

if(flag==0)

{

count++;

if(count<=nof)

victim++;

else

victim=optvictim(i);

pf++;

frm[victim]=ref[i];

for(j=0;j<nof;j++)

printf("%4d",frm[j]);

}

printf("\n Number of page faults: %d",pf);

getch();

}

int optvictim(int index)

{

int i,j,temp,notfound;

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

{

notfound=1;

for(j=index;j<nor;j++)

if(frm[i]==ref[j])

{

notfound=0;

optcal[i]=j;

break;

}

if(notfound==1)

return i;

}

temp=optcal[0];

for(i=1;i<nof;i++)

if(temp<optcal[i])

temp=optcal[i];

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

if(frm[temp]==frm[i])

return i;

return 0;

}

Program 11a):

AIM: Write a program to implement Dynamic allocation of memories in Memory Variable Technique.

#include<stdio.h>

#include<conio.h>

main()

{

int i,m,n,tot,s[20];

clrscr();

printf("Enter total memory size:");

scanf("%d",&tot);

printf("Enter no. of pages:");

scanf("%d",&n);

printf("Enter memory for OS:");

scanf("%d",&m);

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

{

printf("Enter size of page%d:",i+1);

scanf("%d",&s[i]);

}

tot=tot-m;

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

{

if(tot>=s[i])

{

printf("Allocate page %d\n",i+1);

tot=tot-s[i];

}

else

printf("process p%d is blocked\n",i+1);

}

printf("External Fragmentation is=%d",tot);

getch();

}

OUTPUT:

Program 11b):

AIM: Write a program to implement Dynamic allocation of memories in Memory Fixed Technique.

#include<stdio.h>

#include<conio.h>

#include<math.h>

#define MAX 10

int main()

{

int ma,bs,ps,tmp,sbn[MAX]={0},ebn[MAX]={0},count=0,i=0,k,ifrag[MAX]={0};

char ch;

clrscr();

printf("\nEnter total memory available (in MB)");

scanf("%d",&ma);

printf("\nEnter size of each block(in MB)");

scanf("%d",&bs);

while(ma)

{

printf("\nDo u have a program(y/n)");

fflush(stdin);

scanf("%c",&ch);

if((ch!='y') && (ch!='Y'))

{

printf("\nMemory available %d MB",ma);

break;

}

printf("\nEnter the size of program(inMB)");

scanf("%d",&ps);

if(ps>ma)

{

printf("\nMemory required %d\nBUt\nMemory available:%d",ps,ma);

break;

}

count++;

if(!i)

{

sbn[i]=0;

ebn[i]=(ceil((float)ps/bs))-1;

}

else

{

sbn[i]=ebn[i-1]+1;

ebn[i]=sbn[i]+(ceil((float)ps/bs))-1;

}

tmp=((ceil((float)ps/bs)*bs));

ifrag[i]=tmp-ps;

i++;

ma-=tmp;

printf("\nMemory allocated%dMB\nMemory available%dMB",tmp,ma);

printf("\nBlocls\tnum of blocks\tInternal fragmentation(inMB)");

for(k=0;k<count;k++)

printf("\n\n%d-%d\t\t%d\t\t%d",sbn[k],ebn[k],ebn[k]-sbn[k]+1,ifrag[k]);

}

getch();

return 1;

}

OUTPUT:

Program 11c):

AIM: To implement the Memory management policy- Paging.

#include<stdio.h>

#define MAX 50

int main()

{

int page[MAX],i,n,f,ps,off,pno;

printf("\nEnter the no of pages in memory");

scanf("%d",&n);

printf("\nEnter page size");

scanf("%d",&ps);

printf("\nEnter no of frames");

scanf("%d",&f);

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

page[i]=-1;

printf("\nEnter the page table\n");

printf("(Enter frame no as -1 if that page is not present in any frame)\n\n");

printf("\npageno\tframeno\n-------\t-------");

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

{

printf("\n\n%d\t\t",i);

scanf("%d",&page[i]);

}

printf("\n\nEnter the logical address(i.e,page no & offset):");

scanf("%d%d",&pno,&off);

if(page[pno]==-1)

printf("\n\nThe required page is not available in any of frames");

else

printf("\n\nPhysical address(i.e,frame no & offset):%d,%d",page[pno],off);

return 0;

}

OUTPUT:

Program 11d):

AIM: To implement the memory management policy-segmentation.

#include <stdio.h>

#include <conio.h>

#include <math.h>

int sost;

void gstinfo();

void ptladdr();

struct segtab

{

int sno;

int baddr;

int limit;

int val[10];

}st[10];

void gstinfo()

{

int i,j;

printf("\n\tEnter the size of the segment table: ");

scanf("%d",&sost);

for(i=1;i<=sost;i++)

{

printf("\n\tEnter the information about segment: %d",i);

st[i].sno = i;

printf("\n\tEnter the base Address: ");

scanf("%d",&st[i].baddr);

printf("\n\tEnter the Limit: ");

scanf("%d",&st[i].limit);

for(j=0;j<st[i].limit;j++)

{

printf("Enter the %d address Value: ",(st[i].baddr + j));

scanf("%d",&st[i].val[j]);

}

void ptladdr()

{

int i,swd,d=0,n,s,disp,paddr;

clrscr();

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

printf("\n\t SEG.NO\tBASE ADDRESS\t LIMIT \n\n");

for(i=1;i<=sost;i++)

printf("\t\t%d \t\t%d\t\t%d\n\n",st[i].sno,st[i].baddr,st[i].limit);

printf("\n\nEnter the logical Address: ");

scanf("%d",&swd);

n=swd;

while (n != 0)

{

n=n/10;

d++;

}

s = swd/pow(10,d-1);

disp = swd%(int)pow(10,d-1);

if(s<=sost)

{

if(disp < st[s].limit)

{

paddr = st[s].baddr + disp;

printf("\n\t\tLogical Address is: %d",swd);

printf("\n\t\tMapped Physical address is: %d",paddr);

printf("\n\tThe value is: %d",( st[s].val[disp] ) );

}

else

printf("\n\t\tLimit of segment %d is high\n\n",s);

}

else

printf("\n\t\tInvalid Segment Address \n");

}

void main()

{

char ch;

clrscr();

gstinfo();

{

ptladdr();

printf("\n\t Do U want to Continue(Y/N)");

flushall();

scanf("%c",&ch);

}while (ch == 'Y' || ch == 'y' );

getch();

}

Program 10a):

AIM: Write a C program to simulate file organization technique Single Level

#include<stdio.h>

#include<conio.h>

main()

{

int master,s[20];

char f[20][20][20];

char d[20][20];

int i,j;

clrscr();

printf("enter number of directorios:");

scanf("%d",&master);

printf("enter names of directories:");

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

scanf("%s",&d[i]);

printf("enter size of directories:");

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

scanf("%d",&s[i]);

printf("enter the file names :");

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

for(j=0;j<s[i];j++)

scanf("%s",&f[i][j]);

printf("\n");

printf(" directory\tsize\tfilenames\n");

printf("*************************************************\n");

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

{

printf("%s\t\t%2d\t",d[i],s[i]);

for(j=0;j<s[i];j++)

printf("%s\n\t\t\t",f[i][j]);

printf("\n");

}

printf("\t\n");

getch();

}

OUTPUT:

Program 10b):

AIM: Write a C program to simulate file organization technique Two Level

#include<stdio.h>

struct st

{

char dname[10];

char sdname[10][10];

char fname[10][10][10];

int ds,sds[10];

}dir[10];

main()

{

int i,j,k,n;

printf("enter number of directories:");

scanf("%d",&n);

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

{

printf("enter directory %d names:",i+1);

scanf("%s",&dir[i].dname);

printf("enter size of directories:");

scanf("%d",&dir[i].ds);

for(j=0;j<dir[i].ds;j++)

{

printf("enter subdirectory name and size:");

scanf("%s",&dir[i].sdname[j]);

scanf("%d",&dir[i].sds[j]);

for(k=0;k<dir[i].sds[j];k++)

{

printf("enter file name:");

scanf("%s",&dir[i].fname[j][k]);

}

printf("\ndirname\t\tsize\tsubdirname\tsize\tfiles");

printf("\n******************************************************\n");

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

{

printf("%s\t\t%d",dir[i].dname,dir[i].ds);

for(j=0;j<dir[i].ds;j++)

{

printf("\t%s\t\t%d\t",dir[i].sdname[j],dir[i].sds[j]);

for(k=0;k<dir[i].sds[j];k++)

printf("%s\t",dir[i].fname[j][k]);

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

}

printf("\n"); }

}

PROGRAM 9a):

AIM: Write a C Program to implement Sequential File Allocation method.

#include<stdio.h>

void main()

{

int n,i,j,b[20],sb[20],t[20],x,c[20][20];

printf("Enter no.of files:");

scanf("%d",&n);

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

{

printf("Enter no. of blocks occupied by file%d:",i+1);

scanf("%d",&b[i]);

printf("Enter the starting block of file%d:",i+1);

scanf("%d",&sb[i]);

t[i]=sb[i];

for(j=0;j<b[i];j++)

c[i][j]=sb[i]++;

}

printf("Filename\tStart block\tlength\n");

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

printf("%d\t %d \t %d\n",i+1,t[i],b[i]);

}

OUTPUT:

PROGRAM 9b):

AIM: Write a C Program to implement Indexed File Allocation method.

#include<stdio.h>

#include<conio.h>

main()

{

int n,m[20],i,j,sb[20],s[20],b[20][20],x;

clrscr();

printf("Enter no. of files:");

scanf("%d",&n);

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

{ printf("Enter starting block and size of file%d:",i+1);

scanf("%d%d",&sb[i],&s[i]);

printf("Enter blocks occupied by file%d:",i+1);

scanf("%d",&m[i]);

printf("enter blocks of file%d:",i+1);

for(j=0;j<m[i];j++)

scanf("%d",&b[i][j]);

} printf("\nFile\t index\tlength\n");

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

{

printf("%d\t%d\t%d\n",i+1,sb[i],m[i]);

}printf("\nEnter file name:");

scanf("%d",&x);

printf("file name is:%d\n",x);

i=x-1;

printf("Index is:%d",sb[i]);

printf("Block occupied are:");

for(j=0;j<m[i];j++)

printf("%3d",b[i][j]);

getch();

}

OUTPUT:

Program 9c):

Aim: Write a C Program to implement Linked File Allocation method.

#include<stdio.h>

#include<conio.h>

struct file

{

char fname[10];

int start,size,block[10];

}f[10];

main()

{

int i,j,n;

clrscr();

printf("Enter no. of files:");

scanf("%d",&n);

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

{

printf("Enter file name:");

scanf("%s",&f[i].fname);

printf("Enter starting block:");

scanf("%d",&f[i].start);

f[i].block[0]=f[i].start;

printf("Enter no.of blocks:");

scanf("%d",&f[i].size);

printf("Enter block numbers:");

for(j=1;j<=f[i].size;j++)

{

scanf("%d",&f[i].block[j]);

}

printf("File\tstart\tsize\tblock\n");

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

{

printf("%s\t%d\t%d\t",f[i].fname,f[i].start,f[i].size);

for(j=1;j<=f[i].size-1;j++)

printf("%d--->",f[i].block[j]);

printf("%d",f[i].block[j]);

printf("\n");

}

getch();

}