Working With Files

The compiler gives me an error:

Code:

void openInv(struct inventory invDB) 
{
    disk_file = fopen("a:\\may.inv", "rb+");
    if (!disk_file) {
        printf("Error: Disk\n");
        exit(1);
        }
    fread(invDB, sizeof(invDB), 1, disk_file);
    fclose(disk_file);
}

Error:
incompatible type for argument 1 of `fread'

Code:

  // Should be : void openInv(struct inventory *invDB), because you want it to be stored in a variable outside of the function scope
void openInv(struct inventory invDB) 
{
// what is the type of disk_file? should be : FILE* disk_file = ...
    disk_file = fopen("a:\\may.inv", "rb+");
// mainly a personal preference, but it should be : if(disk_file != NULL), 
  //as NULL is what is returned on error by fopen and you can't depend on NULL being
  // defined as 0 on all computers
    if (!disk_file) {
        printf("Error: Disk\n");
        exit(1);
        }

   // should be : fread((void*)invDB,sizeof(invDB), . . .); because 
  //fread needs a void * for the first argument. NOTE: for this part 
  //to work, you need to correct the mistakes I labeled above,
  // because currently, even if you obeyed the first correction you 
  // would be getting alot of other syntax errors
     fread(invDB, sizeof(invDB), 1, disk_file);
    fclose(disk_file);
}

EDIT: I presume you know about pointers... if not, I suggest reading the tutorials on this site.

Oh, this is up at the top aswell:

Code:

FILE * disk_file;

Also, invDB is an array of a struct.

whoah, post your whole code, cause you are using global variables... a big no-no.