File Menu c PROGRAM

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

int main()
{
FILE *fp;
FILE *out;

char another,choice;

struct emp {
char name[40];
int age;
float bs;
};

struct emp e;
char empname[40];

int recsize;

char buffer[25];

clrscr();

fp=fopen("emp.dat","rb+");

if (fp==NULL)
{
fp=fopen("emp.dat","wb+");
if (fp==NULL)
{
printf("Cannot open the main file");
exit(1);
}
}


recsize=sizeof(e);

while(1)
{
printf("\n1. Add Records");
printf("\n2. List Records");
printf("\n3. Modify Records");
printf("\n4. Delete Records");
printf("\n5. Exit");
printf("\nEnter Your Choice");
fflush(stdin);
choice=getche();

switch(choice)
{
case '1':
fseek(fp,0,SEEK_END);
another='Y';
while(another=='y' || another=='Y')
{
printf("\nEnter name , age and basic Salary");
scanf("%s%d%f",e.name,&e.age,&e.bs);
// fprintf(fp,"%s%d%f",e.name,e.age,e.bs);
fwrite(&e,recsize,1,fp);
printf("\nAdd Another Reccord(Y/N)");
fflush(stdin);
another=getche();
}
break;
case '2':
rewind(fp);
//fseek(fp,0,SEEK_SET);

while(fread(&e,recsize,1,fp)==1)
printf("%s %d %f\n",e.name,e.age,e.bs);
break;
case '3':
another='y';
while(another=='y' || another=='Y')
{
printf("\nEnter the name of employee to modify");
scanf("%s",empname);

rewind(fp);
while(fread(&e,recsize,1,fp)==1)
{
if (strcmp(e.name,empname)==0)
{
printf("\nEnter new name, age, basic "\
"salary");
scanf("%s%d%f",e.name,&e.age,&e.bs);
fseek(fp,-recsize,SEEK_CUR);
fwrite(&e,recsize,1,fp);
break;
}
}
printf("\nModify Another record (Y/N)");
fflush(stdin);
another=getche();
}
break;
case '4':
another='Y';

while(another=='y' || another=='Y')
{
printf("\nEnter the name of employee to delete");
scanf("%s",empname);

tmpnam(buffer);
puts(buffer);
out=fopen(buffer,"wb+");
if (out==NULL)
{
printf("\nCannot open the temp file");
exit(2);
}

rewind(fp);
while(fread(&e,recsize,1,fp)==1)
{
if (strcmp(e.name,empname)!=0)
fwrite(&e,recsize,1,out);
}
fclose(fp);
fclose(out);
remove("EMP.DAT");
if (rename(buffer,"EMP.DAT") == 0)
printf("\nRenamed");
else
printf("\nCannot rename");

fp=fopen("EMP.DAT","rb+");

printf("\nDelete Another Record (Y/N)");
fflush(stdin);
another=getche();
}
break;
case '5':
fclose(fp);
exit(0);
}
}
}