please help!! have some problems with my address book
 

i need to write a program that is acting as a simple personal address book with the record of name,email and phone numbers.
The range of function should have:
searching existing records.
adding new records.
deleting existing records.
i need to include the last update date and time of the record in the form of dd-mm-yyyy,hh:mm:ss(it has to be updated by th program automatically) and i don't really know how. Can't someone help me? I'm new to C language. And there is some problem in the delete function, edit function and the file operation.
Below is the code of what my group members and I did so far

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <time.h>



enum {

    MAXLEN=255

};



typedef struct list {

    char name[MAXLEN];

    char address[MAXLEN];

    char phone[MAXLEN];

    struct list *next;

} ADDRESS;



void add_to_list (void);

void delete_from_list (void);

void search_name (void);

void list_names (void);

void quit_program (void);

void edit(void);

ADDRESS *hol= NULL;



int main()

{

    char input[MAXLEN];





    while (1) {

        printf ("What you want to do?\n");

        printf("a.Search\n");

        printf("b.Add\n");

        printf("c.Delete\n");

        printf("d.Edit\n");

        printf("e.Display Option\n");

        printf("f.Exit\n");





        fgets (input, MAXLEN,stdin);

        switch (input[0]) {

            case ('a'):

            case ('A'):

                search_name();

                break;

            case ('b'):

            case ('B'):

                add_to_list();

                break;

            case ('c'):

            case ('C'):

                delete_from_list();

                break;

            case ('d'):

            case ('D'):

                edit();

                break;

            case ('e'):

            case ('E'):

                quit_program();

                return (0);

            default:

                printf ("Unknown command\n");

        }



    }

    return 0;

}



void add_to_list (void)



{

    ADDRESS *new_name;



    new_name= (ADDRESS *)malloc (sizeof (ADDRESS));

    if (new_name == NULL) {

        printf ("Out of memory!\n");

        exit (-1);

    }



    printf ("Name> ");

    fgets (new_name->name, MAXLEN, stdin);

    printf ("Address> ");

    fgets (new_name->address, MAXLEN, stdin);

    printf ("Tel> ");

    fgets (new_name->phone, MAXLEN, stdin);

    /* Chain the new item into the list */

    new_name->next= hol;

    hol= new_name;

}



void delete_from_list (void)



{

    ADDRESS *del_ptr;   /* Pointer to find name to delete */

    ADDRESS *prev_ptr;  /* Pointer to name BEFORE this name */

    char del_name[MAXLEN]; /* Name to delete */



    printf ("Name> ");

    fgets (del_name, MAXLEN, stdin);



    if (hol == NULL) {

        printf ("No list to delete from\n");

        return;

    }

    if (strcmp(hol->name, del_name) == 0) {

        del_ptr= hol;

        hol= hol->next;

        free(del_ptr);

        return;

    }



    prev_ptr= hol;

    while (prev_ptr->next != NULL) {



        if (strcmp(prev_ptr->next->name,del_name) == 0) {

            del_ptr= prev_ptr->next;

            prev_ptr->next= del_ptr->next;

            free(del_ptr);

            return;

        }

        prev_ptr= prev_ptr->next;

    }

    printf ("Name not found!\n");

}



void search_name (void)





{

    char name[MAXLEN];  /* Name to look for */

    ADDRESS *search_ptr;

    printf ("Name> ");

    fgets (name, MAXLEN, stdin);

    search_ptr= hol;

    while (search_ptr != NULL) {

        if (strcmp (search_ptr->name, name) == 0) {

            printf ("Address: %s", search_ptr->address);

            printf ("Tel: %s", search_ptr->phone);

            return;

        }

        search_ptr= search_ptr->next;

    }

    printf ("No such name\n");

}



void list_names (void)



{

    ADDRESS *tmp_ptr; /* Traverses list */

    printf ("All names in address book:\n");

    tmp_ptr= hol;

    while (tmp_ptr != NULL) {

        printf ("%s",tmp_ptr->name);

        tmp_ptr= tmp_ptr->next;

    }

}



void quit_program (void)

{

    ADDRESS *del_ptr;



    while (hol != NULL) {

       del_ptr= hol;

       hol= hol->next;

       free(del_ptr);

    }

}





void edit (void)



{

    ADDRESS *edi_ptr;   /* Pointer to find name to edit */

    ADDRESS *prev_ptr;  /* Pointer to name BEFORE this name */

    char edi_name[MAXLEN]; /* Name to edit */



    printf ("Name> ");

    fgets (edi_name, MAXLEN, stdin);



    if (hol == NULL) {

        printf ("No list to edit from\n");

        return;

    }

    if (strcmp(hol->name, edi_name) == 0) {

        edi_ptr= hol;

        hol= hol->next;

        free(edi_ptr);

        return;

    }



    prev_ptr= hol;

    while (prev_ptr->next != NULL) {



        if (strcmp(prev_ptr->next->name,edi_name) == 0) {

            edi_ptr= prev_ptr->next;

            prev_ptr->next= edi_ptr->next;

            free(edi_ptr);

            return;

        }

        prev_ptr= prev_ptr->next;

    }

    printf ("Name not found!\n");

}

Re: please help!! have some problems with my address book
 

>>i need to include the last update date and time of the record in the form of dd-mm-yyyy,hh:mm:ss(it has to be updated by th program automatically) and i don't really know how.

Just add another field called UpdateDateTime (or whatever you want to call it) to each record which would be time_t. When you write a record get the system's time using time() function from time.h and save it to the field along with all the other information. If you don't want to save the date/time as an integer then you can call localtime() that returns a string and save that, but it will take up alot more space in the file.

Re: please help!! have some problems with my address book
 

oh..ok..thank you so much!!now i have no problem with the time and date thingy..but still have another question that is on exiting the program all active records must be stored in a file eg. phonebook.txt. On start up, the program should read the stored file and display records on the screen.If the file does't exist, have to create a new one to store information. The program should prompt the user for input to perform the functions listed above.
Which function i need to use? and how?

Re: please help!! have some problems with my address book
 

you need to use FILE*. On program startup, attempt to open the file for reading. If successful, then do what you mentioned. If not, then the file doesn't exist.

>>Which function i need to use? and how?
This is just normal file i/o stuff that should be explained in your textbook.

fopen() -- opens the file
fread() and fgets() -- reads the file
fwrite() -- writes the file
fseek() -- move file pointer around the file
fclose() -- close the file

Re: please help!! have some problems with my address book
 

now my program can be saved, however when i want to delete a contact, it can't be deleted completely, what's wrong?

void delete_from_list (void)



{

    ADDRESS *del_ptr;   /* Pointer to find name to delete */

    ADDRESS *prev_ptr;  /* Pointer to name BEFORE this name */

    char del_name[MAXLEN]; /* Name to delete */



    printf ("Name> ");

    fgets (del_name, MAXLEN, stdin);



    if (hol == NULL) {

        printf ("No list to delete from\n");

        return;

    }

    if (strcmp(hol->name, del_name) == 0) {

        del_ptr= hol;

        hol= hol->next;

        free(del_ptr);

        return;

    }



    prev_ptr= hol;

    while (prev_ptr->next != NULL) {



        if (strcmp(prev_ptr->next->name,del_name) == 0) {

            del_ptr= prev_ptr->next;

            prev_ptr->next= del_ptr->next;

            free(del_ptr);

            return;

        }

        prev_ptr= prev_ptr->next;

    }

    printf ("Name not found!\n");

}