Untitled

#include <stdio.h> ///for input output functions like printf, scanf 
 #include <stdlib.h> 
 #include <conio.h> 
 #include <string.h>  ///string operations 
  
 #include "navigation.h" 
 #include "user_interface.h" 
  
 int main() 
 { 
     displayUserInterface(); 
  
     FILE *fp, *ft; /// file pointers 
     char another, choice; 
  
     /** structure that represent a employee */ 
     struct employee 
     { 
         char name[40]; 
         int age; 
         float basicSalary; 
     }; 
  
     struct employee activeEmployee; /// structure variable creation 
  
     char employeeName[40]; /// string to store name of the employee 
  
     long int recordSize; /// size of each record of employee 
  
     /** open the file in binary read and write mode 
     * if the file EMP.DAT already exists then it open that file in read write mode 
     * if the file doesn't exit it simply create a new copy 
     */ 
     fp = fopen("EMP.DAT","rb+"); 
     if(fp == NULL) 
     { 
         fp = fopen("EMP.DAT","wb+"); 
         if(fp == NULL) 
         { 
             printf("Cannot open file"); 
             exit(1); 
         } 
     } 
  
     /// sizeo of each record i.e. size of structure variable activeEmployee 
     recordSize = sizeof(activeEmployee); 
  
     /// infinite loop continues until the break statement encounter 
     while(1) 
     { 
  
         fflush(stdin); /// flush the input buffer 
         choice  = getche(); /// get the input from keyboard 
         switch(choice) 
         { 
         case '1':  /// if user press 1 
             system("cls"); 
             fseek(fp,0,SEEK_END); /// search the file and move cursor to end of the file 
             /// here 0 indicates moving 0 distance from the end of the file 
  
             another = 'y'; 
             while(another == 'y')  /// if user want to add another record 
             { 
                 printf("\nEnter name: "); 
                 scanf("%s",activeEmployee.name); 
                 printf("\nEnter age: "); 
                 scanf("%d", &activeEmployee.age); 
                 printf("\nEnter basic salary: "); 
                 scanf("%f", &activeEmployee.basicSalary); 
  
                 fwrite(&activeEmployee,recordSize,1,fp); /// write the record in the file 
  
                 printf("\nAdd another record(y/n) "); 
                 fflush(stdin); 
                 another = getche(); 
             } 
             break; 
         case '2': 
             system("cls"); 
             rewind(fp); ///this moves file cursor to start of the file 
             while(fread(&activeEmployee,recordSize,1,fp)==1)  /// read the file and fetch the record one record per fetch 
             { 
                 printf("\n%s %d %.2f",activeEmployee.name,activeEmployee.age,activeEmployee.basicSalary); /// print the name, age and basic salary 
             } 
             getch(); 
             break; 
  
         case '3':  /// if user press 3 then do editing existing record 
             system("cls"); 
             another = 'y'; 
             while(another == 'y') 
             { 
                 printf("Enter the employee name to modify: "); 
                 scanf("%s", employeeName); 
                 rewind(fp); 
                 while(fread(&activeEmployee,recordSize,1,fp)==1)  /// fetch all record from file 
                 { 
                     if(strcmp(activeEmployee.name,employeeName) == 0)  ///if entered name matches with that in file 
                     { 
                         printf("\nEnter new name,age and bs: "); 
                         scanf("%s%d%f",activeEmployee.name,&activeEmployee.age,&activeEmployee.basicSalary); 
                         fseek(fp,-recordSize,SEEK_CUR); /// move the cursor 1 step back from current position 
                         fwrite(&activeEmployee,recordSize,1,fp); /// override the record 
                         break; 
                     } 
                 } 
                 printf("\nModify another record(y/n)"); 
                 fflush(stdin); 
                 another = getche(); 
             } 
             break; 
         case '4': 
             system("cls"); 
             another = 'y'; 
             while(another == 'y') 
             { 
                 printf("\nEnter name of employee to delete: "); 
                 scanf("%s",employeeName); 
                 ft = fopen("Temp.dat","wb");  /// create a intermediate file for temporary storage 
                 rewind(fp); /// move record to starting of file 
                 while(fread(&activeEmployee,recordSize,1,fp) == 1)  /// read all records from file 
                 { 
                     if(strcmp(activeEmployee.name,employeeName) != 0)  /// if the entered record match 
                     { 
                         fwrite(&activeEmployee,recordSize,1,ft); /// move all records except the one that is to be deleted to temp file 
                     } 
                 } 
                 fclose(fp); 
                 fclose(ft); 
                 remove("EMP.DAT"); /// remove the orginal file 
                 rename("Temp.dat","EMP.DAT"); /// rename the temp file to original file name 
                 fp = fopen("EMP.DAT", "rb+"); 
                 printf("Delete another record(y/n)"); 
                 fflush(stdin); 
                 another = getche(); 
             } 
             break; 
         case '5': 
             fclose(fp);  /// close the file 
             exit(0); /// exit from the program 
         } 
     } 
     return 0; 
 }