Question

I am writing a program that accepts a file with database entries in it. The entries are all in the same format, with the data in the same order. The first number in the file is the number of entries. Then the data looks like this:
LastName FirstName StudentID age year GPA expectedGraduationDate

Ex:
Doe John 12345678 23 freshman 4.0 2013

My issue is with the year value. We are supposed to declare it as type ‘class’, which is supposed to be enum class{freshman, sophomore, junior, senior, grad};

I have a header file with the following declaration:

typedef enum {firstYear, sophomore, junior, senior, grad} class;

Then my main file:

#include <stdio.h>
#include <stdlib.h>
#include "class.h"

int main(int argc, char *argv[]){

typedef struct{
        int DBrecordID;         //ID for each entry, range 0-319
        char *last;             //student last name
        char *first;            //student first name
        char studentID[8];      //student ID
        int age;                //student age
        class year;             //year in school
        float gpa;              //GPA
        int expGradYear;        //expected graduation year
}DBrecord;
int numEntries;
DBrecord **record;
char buffer[80];
FILE *fpt;
int c, i;
int j = 0;

//check for invalid file arguments
if(argc != 2){
        printf("Number of arguments is invalid\n");
        exit(1);
}

//error if unable to open file
if((fpt = fopen(argv[1], "r")) == NULL){
        printf("Error: Couldn't open file.\n");
        exit(1);
}

//set file pointer to read passed file
fpt = fopen(argv[1], "r");

//scan first int in file and assign to numEntries
//fscanf(fpt, "%d", &numEntries);

//allocate memory for structures, each is 36 bytes
*record = malloc (sizeof (DBrecord) * numEntries);

//loop through each DB entry
do{
        for(i=0; i<numEntries; i++){
                numEntries = record[i]->DBrecordID;
                do{
                        c=fgetc(fpt);
                        buffer[j++] = c;
                }while(c != ' ');
                        strcpy(record[i]->last, buffer);
                        j=0;
                do{
                        c=fgetc(fpt);
                        buffer[j++] = c;
                }while(c != ' ');
                        strcpy(record[i]->first, buffer);
                        j=0;
                do{
                        c=fgetc(fpt);   
                        buffer[j++] = c;
                }while(c != ' ');
                        strcpy(record[i]->studentID, buffer);
                        j=0;
                do{
                        c=fgetc(fpt);
                        memcpy(c, buffer[j++], 1);
               }while(c != ' ');
                        memcpy(buffer, record[i]->year, 4);
                        j=0;
                do{
                        c=fgetc(fpt);
                        buffer[j++] = c;
                }while(c != ' ');
                        memcpy(buffer, record[i]->gpa, 4);
                        j=0;
                do{  
                        c=fgetc(fpt);
                        buffer[j++] = c;
                }while(c != ' ' || c != '\n');
                        memcpy(buffer, record[i]->expGradYear, 4);
                        j=0;
         }
}while(c != EOF);

return 0;
}

*Updated errors

main.c:75: warning: passing arg 1 of `memcpy’ makes pointer from integer without a cast

main.c:75: warning: passing arg 2 of `memcpy’ makes pointer from integer without a cast

main.c:77: incompatible type for argument 2 of `memcpy’

main.c:83: incompatible type for argument 2 of `memcpy’

main.c:89: warning: passing arg 2 of `memcpy’ makes pointer from integer without a cast

main.c:94: parse error before “DBrecord”

So I’m assuming I can’t do what I’m trying to do with memcpy, or I’m just doing it wrong. Suggestions?

Answer 1

There quite a few errors in the program but for a start

1) record should be of type DBrecord* not DBrecord**

2) strcpy takes destination as the first argument so this wouldn’t work
strcpy(buffer, record[i]->last);

3) you also need to allocate memory for record[i]->last

4) strcpy is used to copy strings so if you wan’t to store to float or int i.e. gpa etc you need to use memcpy also the value from buffer should be converted using strol strod

also would recommend to get hold of this book K&R it would be really helpful overtime