Menu type program - c

Question

I have an assignment to write a program for supporting an art gallery in C. It has to be menu based program using lists. I wrote the first function of the menu and I need some help writing the other three. So I have a structure of an unique code of the painting, author's name, painting's name, price, year of the painting. I have to create a function deleting a painting using the unique code, print out all the info about every painting and modifying a painting again using said code. The data has to be in a dynamic type structure using a linked list. This is the program so far.
#include <stdio.h>
void addPainting(void);
void erasePainting(void);
void printData(void);
void modifyData(void);
int main()
{
struct paintings
{
char code[20];
char name[50];
char paintingName[50];
double price;
int year;
}painting[100];
int choice;
do
{
printf("Menu\n");
printf("To add a painting press 1.\n");
printf("To erase a painting press 2.\n");
printf("To print data for all paintings by authors alphabetically press 3.\n");
printf ("To modify data for a painting press 4.\n");
printf("To exit the program press 5.\n");
scanf("%d",&choice);
switch(choice)
{
case 1:
{
addPainting();
break;
}
case 2:
{
erasePainting();
break;
}
case 3:
{
printData();
break;
}
case 4:
{
modifyData();
break;
}
default: printf ("Wrong choice. Try again\n");
break;
}
}while (choice !=5);
void addPainting()
{
FILE *fp;
struct paintings painting;
printf("Enter code:");
scanf("%s", &painting.code);
printf("Enter the name of the author:");
scanf("%s", &painting.name);
printf("Enter the name of the painting:");
scanf("%s", &painting.paintingName);
printf("Enter price:");
scanf("%lf", &painting.price);
printf("Enter the year of creation:");
scanf("%d", &painting.year);
if ((fp=fopen("paintings","wb"))==NULL)
exit(1);
if ((fwrite (&painting,sizeof(painting),1,fp)!=1))
exit(2);
fclose(fp);
}
}

Answer 1

First problem: You are missing the closing brace ( } ) for the main() function. (but I am sure you knew that)
The reason for the struct size error is that you are attempting to create an instance of struct painting in the void addPainting() function, when it was created with local scope in the main function, and therefore it is not visible to the function. Create struct painting with global scope if you want to use it this way:
This will build (and run) but only for the functions defined, the others are commented out. There are other problems you will have to work out, or ask about.
EDITED to fix scanf() statements, show use of fopen()/fclose(), create and write strings using sprintf()/fputs()...
void addPainting(void);
//void erasePainting(void);
//void printData(void);
//void modifyData(void);
typedef struct //created with global scope, visible to all functions
{
char code[20];
char name[50];
char paintingName[50];
double price;
int year;
}PAINTING;
PAINTING painting[100];//array of instance of PAINTING
#define PATH "C:\\play\\painting.txt" //edit to your need
int main()
{
int choice;
do
{
printf("Menu\n");
printf("To add a painting press 1.\n");
printf("To erase a painting press 2.\n");
printf("To print data for all paintings by authors alphabetically press 3.\n");
printf ("To modify data for a painting press 4.\n");
printf("To exit the program press 5.\n");
scanf("%d",&choice);
switch(choice)
{
case 1:
{
addPainting();
break;
}
case 2:
{
//erasePainting();
break;
}
case 3:
{
//printData();
break;
}
case 4:
{
//modifyData();
break;
}
default: printf ("Wrong choice. Try again\n");
break;
}
}while (choice !=5);
}
void addPainting(void)
{
FILE *fp;
char stringToWrite[80];
//Note: this function could be prototyped with an int argument
// to be used as an index for the array arguments of your
// structure. Currently, the indexes are hard-coded to 0,
printf("Enter code:");
//scanf("%s", &painting[0].code);
scanf("%s", painting[0].code); //& not needed for char array (char *) et. al.
printf("Enter the name of the author:");
scanf("%s", painting[0].name);
printf("Enter the name of the painting:");
scanf("%s", painting[0].paintingName);
printf("Enter price:");
scanf("%lf", &painting[0].price);
printf("Enter the year of creation:");
scanf("%d", &painting[0].year);
fp = fopen (PATH, "a");//open for create/append text file (not write binary, "wb")
if(fp)
{
sprintf(stringToWrite, "Painting Code is: %s\n", painting[0].code);
fputs(stringToWrite, fp);
// do others same way...
//...
fclose(fp);
}
}