/*
 * filew4.c
 */
#include <stdio.h>

int getans(void);

int main(void)
{
  FILE * fp; // declare file pointer:fp
  char first[15], last[15], phone[20], email[30]; // declare char arrays
  char addressbook[10]; // declare char array 
  printf("Enter the name of a new address book: "); // prompt for input
  scanf("%s", addressbook); // read from stdin
                            // interpret as string
                            // assign to elements of array addressbook

  if( (fp=fopen(addressbook,"w")) == NULL ) // open file file for writing
                                             // assign file handle address to fp
                                             // if address is NULL, do block 
  {
    printf("Can't open file %s.\n", addressbook); // print error
    return 1; // return 1 to calling program
  }
 
  do 
  {
    printf("First Name: ");
    scanf(" %s", first);
    
    printf("Last Name: ");
    scanf(" %s", last);

    printf("Phone Number: ");
    scanf(" %s", phone);

    printf("Email Address: ");
    scanf(" %s", email);

    getchar(); // clear input buffer

    fprintf(fp, " %s %s", first, last);
    fprintf(fp, " %s %s\n", phone, email);

    printf("Do you wish to enter another person's information? (y/n): ");
  }
  while( getans() ); 

  fclose(fp);

  printf("The file %s written and closed.\n", addressbook);

  return 0;
}
//// Functions
int getans(void) // header: takes nothing, returns int
{
  char cc;
  if( (cc=getchar()) == 'y' ) // read from stdin, assign to cc
                              // if cc == 'y', do block
  {
    getchar(); // clear input buffer
    return 1; // they want to enter more people
  }
  else
  {
    return 0;  // they don't want to enter more people 
  }
}