Help me in this file handling

Question

Read the folowing...

#include<stdio.h>
#include<stdlib.h>
#include<conio.h>
int main()
{char c,filename[10];
FILE *f1,*f2;
int n;
int temp=1;long offset;
printf("enter filename:\n");
scanf("%s",filename);
printf("enter offset value:\n");
scanf("%ld",&offset);
f1=fopen(filename,"w");
printf("enter text in f1:\n");
while((c=getchar())!=-1)
putc(c,f1);
n=ftell(f1);
printf("n=%d\n",n);
fclose(f1);
f1=fopen(filename,"r");
f2=fopen("text","w");

if(offset>0&&offset<n)
fseek(f1,offset,0);
else if(offset<0)
fseek(f1,offset,2);

while((c=getc(f1))!=-1)
putc(c,f2);
fclose(f2);
f2=fopen("text","r");
while((c=getc(f2))!=-1)
printf("%c",c);
fclose(f2);

}

// Why the program is setting the offset value 2 less than what is being provided

Answer 1

please write this on code play ground and link it here