Page 141 - DCAP507_SYSTEM_SOFTWARE

Unit 9: Design of an Absolute Loader

Notes
Example: Write a C program to execute pass 1 of direct linking loader.
#include<stdio.h>
#include<conio.h>
#include<stdlib.h>
#include<string.h>
#define MAX 10
struct estab
{ char csect[10];
char sym_name[10];
long int add;
int length;
}table[MAX];
void main()
{ FILE *fp1, *fp2;
char input[10];
long int i, count =0, start, length, loc;
clrscr();
fp1=fopen("linkin.dat", "r");
fp2=fopen("linkout.dat", "w");
printf("Enter the location where the program has to be loaded:");
scanf("%lx", &start);
fprintf(fp2, "CSECT \t symname \t address \t length\n");
rewind(fp1);
while(!feof(fp1))
{
fscanf(fp1, "%s", input);
if(strcmp(input, "H")==0)
{
fscanf(fp1, "%s", input);
strcpy(table[count].csect, input);
strcpy(table[count].sym_name, "");
fscanf(fp1, "%s", input);
table[count].add=atoi(input)+start;
fscanf(fp1, "%s", input);
length=atoi(input);
table[count++].length=atoi(input);
fscanf(fp1, "%s", input);
}
if(strcmp(input, "D")==0)

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