#include <stdio.h>
struct emp
  {
    char name[40] ;
    int age ;
    float bs ;
  };
main( )
{
  FILE *fp, *ft ;
  char another, choice ;
  struct emp e ;
  char empname[40] ;
  int recsize ;
  fp = fopen ( "EMP.DAT", "rb+" ) ;
  if ( fp == NULL )
  {
    fp = fopen ( "EMP.DAT", "wb+" ) ;
    if ( fp == NULL )
    {
      printf( "Cannot create a file" ) ;
      system("pause");
      exit(0);
    }
  }
  recsize = sizeof ( e ) ;
  while ( 1 )
  {
    system("cls");   
    printf ( "1. Add Records" ) ;
    printf ( "2. List Records" ) ;
    printf ( "3. Modify Records" ) ;
    printf ( "4. Delete Records" ) ;
    printf ( "0. Exit" ) ;
    printf ( "Your choice" ) ;
    fflush ( stdin ) ;
    choice = getche( ) ;
    switch ( choice )
    {
      case '1' :
      fseek ( fp, 0 , SEEK_END ) ;
      another = 'Y' ;
      while ( another == 'Y' )
      {
        printf ( "\nEnter name, age and basic sal. " ) ;
        scanf ( "%s %d %f", e.name, &e.age, &e.bs ) ;
        fwrite ( &e, recsize, 1, fp ) ;
        printf ( "\nAdd another Record (Y/N) " ) ;
        fflush ( stdin ) ;
        another = getche( ) ;
      }
      break ;
      case '2' :  
      rewind ( fp ) ;
      while ( fread ( &e, recsize, 1, fp ) == 1 )
        printf ( "\n%s %d %f", e.name, e.age, e.bs ) ;
      break ;
      case '3' :
      another = 'Y' ;
      while ( another == 'Y' )
      {
        printf ( "\nEnter 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 & bs" ) ;
            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' )
      {
        printf ( "\nEnter name of employee to delete " ) ;
        scanf ( "%s", empname ) ;
        ft = fopen ( "TEMP.DAT", "wb" ) ;
        rewind ( fp ) ;
        while ( fread ( &e, recsize, 1, fp ) == 1 )
        {
          if ( strcmp ( e.name, empname ) != 0 )
          fwrite ( &e, recsize, 1, ft ) ;
        }
        fclose ( fp ) ;
        fclose ( ft ) ;
        remove ( "EMP.DAT" ) ;
        rename ( "TEMP.DAT", "EMP.DAT" ) ;
        fp = fopen ( "EMP.DAT", "rb+" ) ;
        printf ( "Delete another Record (Y/N) " ) ;
        fflush ( stdin ) ;
        another = getche( ) ;
      }
      break ;
      case '0' :
        fclose ( fp ) ;
        exit(0) ;
      default:
        printf("enter correct choice \n");        
    } // switch
  } // while(1)
}//main