Tokenizing file input and storing data in struct - c

Question

What I am trying to do is to read input from file which is in the format of Data1;Data2;Data3;Data4;Data5 I want to tokenize this string, and store each of these separate pieces of information in a structure such as;
struct example {
char data1[10];
char data2[10];
char data3[10];
char data4[10];
char data5[10];
};
Here's what I have for my input function so far:
void userInput() { // I will need to change return type
FILE *file;
char buffer[BUFFER_SIZE];
struct example data[5];
file = fopen(DATA, "r");
if(file == NULL) {
printf("Error opening data file.\n");
}
while(fgets(buffer, BUFFER_SIZE, file) != null) {
//tokenize strings, and add to struct here
}
}
I realize that in my while function I will need something like:
....
char *token = NULL;
token = strtok(string, ";");
while(token != NULL) {
// add to struct here
token = strtok(NULL, ";");
}
Could someone explain how I would loop through my struct to add this? Or if I'm even going about this the proper way?

Answer 1

You have two things you want to iterate over. I assume each line of input corresponds to a different struct example. Then, you want to iterate over each field in your structure. You need a counter to iterate over your data array, and then you need a mechanism to iterate over the fields. I would use a temporary array to accomplish that:
int i = 0;
while(fgets(buffer, BUFFER_SIZE, file) != null && i < 5) {
char *fields[] = {
data[i].data1, data[i].data2, data[i].data3,
data[i].data4, data[i].data5
};
size_t lengths[] = {
sizeof(data[i].data1), sizeof(data[i].data2), sizeof(data[i].data3),
sizeof(data[i].data4), sizeof(data[i].data5)
};
char *token = NULL;
int j = 0;
token = strtok(string, ";");
while(token != NULL && j < 5) {
snprintf(fields[j], lengths[j], "%s", token);
token = strtok(NULL, ";");
++j;
}
++i;
}

Answer 2

If you want to use a struct, you need some sort of counter to differentiate between your structure elements. Something like:
int x = 0;
while(token != NULL) {
token = strtok(NULL, ";");
// add to struct here
if (x == 0){
data1 = token;
}else if (x == 1){
data2 = token;
}else if (...)
// ... keep going
x++;
}