ALP in line code for displaying boot sector of floppy and boot record of hard disk.

ALP in line code for displaying boot sector of floppy and boot record of hard disk.



#include<stdio.h>
#include<conio.h>

void main()
{
    int i;
    char buffer[512],*ptr;
    clrscr();

    asm{
    mov ah,0x1c                          ;function for absolute read disk
    mov al,0                     ;drive number
    mov cx,0x001                 ;number of sectors to read
    mov dx,0                     ;starting sector
    lea bx,buffer                    ;address of buffer
    int 0x0025

    jnc succ                     ;if successful then no carry
       }
    printf("\n Error reading floppy drive ");
    getch();

    succ : ptr = buffer;             ;ptr contains address of buffer
        
    ptr = ptr + 3;
    printf("\n OEM Name & Version is : ");
    for(i=0;i<8;i++,ptr++)
      {
      printf("%c",*ptr);
      }

    ptr = buffer + 0x0b;
    printf("\n Byte/Sector is : %d ",*(int *)ptr);

    ptr = buffer + 0x0d;
    printf("\n Sectors/Allocation unit is : %d ",*(int *)ptr);

    ptr = buffer + 0x10;
    printf("\n Number of FATs are : %d ",*ptr);

    ptr = buffer + 0x11;
    printf("\n Number of root directory entries are : %d ",*(int *)ptr);

    ptr = buffer + 0x13;
    printf("\n Total number of sectors in logical volume are : %d ",*(int *)ptr);

    ptr = buffer + 0x15;
    printf("\n Media descriptor address byte is : %2x ",(unsigned char)*ptr);

    ptr = buffer + 0x16;
    printf("\n Number of sectors/FAT are : %d ",*(int *)ptr);

    ptr = buffer + 0x18;
    printf("\n Sectors/track is : %d ",*(int *)ptr);

    ptr = buffer + 0x1A;
    printf("\n Number of heads are : %d ",*(int *)ptr);

    getch();
}

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Program to read file from flopy disk (FAT).

Program to read file from flopy disk (FAT).


#include<stdio.h>
#include<conio.h>
#include<string.h>
#include<dos.h>
#include<process.h>

struct dir
{
    char filename[8];
    char ext[3];
    char x1[15];
    int start_cluster;
    char x2[4];
};

void main()
{
    int flag=0,i,j;
    struct dir d[224];
    char arr[512];
    char file[8];
    char ext1[3];
    int logical,physical;

    clrscr();

    printf("\n Enter file name : ");
    scanf("%s",file);
    printf("\n Enter file extension : ");
    scnaf("%s",ext1);

    asm{
    mov al,0
    mov cx,14
    mov dx,19
    lea bx,d
    int 0x25
    }

    for(i=0;i<224;i++)
    {
    for(j=0;j<8;j++)
    {
        if(d[i].filename[j]==' ')
        {
        d[i].filename[j]='\0';
        }
    }
    if(strcmpi(d[i].filename,file)==0)
    {
        printf("\n File name found ");
        d[i].ext[3]='\0';

        if(strcmpi(d[i].ext,ext1)==0)
        {
        printf("\n Extension found ");
        flag=1;
        break;
        }
        else
        {
        printf("\n Extension not found ");
        getch();
        exit(1);
        }
    }
    }

    if(flag==0)
    {
    printf("\n File not found ");
    getch();
    exit(1);
    }

    logical=d[i].start_cluster;
    printf("\n Starting cluster number is : %d ",logical);
    physical=logical+31;

    if(physical<4095)
    {
    asm{
        mov al,0
        mov cx,1
        mov dx,physical
        lea bx,arr
        int 0x25
    }
    }

    printf("\n Contents of file are : \n ");
    printf("%s",arr);
    getch();
}

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