Search code examples
ccsvatoi

using atoi parsing a csv file

I'm writing a program that parses a csv file with the following format: 

hotdog,10,2,1.5

bun,10,2,0.5

The code should strip each line of the file, and as of right now I'm just trying to print the values to make sure the format is correct. My problem is with correctly interpreting the number data - instead of printing the integer values in the csv file, the program is printing zeroes. The program properly parses the first field of each record in the csv, so I think the problem has to do with my formatting of atoi. Here's the code I've written:

char buffer[512]; //512 byte buffer holds the 10 food item names
char* currentLine = buffer; //a temporary pointer to hold the current line read from the csv file

FILE* fp = fopen("inventory.csv", "rw"); //open the inventory.csv file with read and write capabilities.
int i = 0; //counter
while(fgets(currentLine, 1024, fp) != NULL){
    printf("%s\n", strtok(currentLine, ",")); //get first field. Should be the food name.
    printf("%d\t", atoi(strtok(currentLine, ","))); //get second field. Should be stock amount
    printf("%d\t", atoi(strtok(currentLine, ","))); //get third field.
    printf("%f\n", atof(strtok(currentLine, ","))); //get forth field.
    i++;
}
fclose(fp);

Running that as is produces the following output:

hotdog
0   0   0.000000
bun
0   0   0.000000

Is the issue with my formatting of atoi?

Solution

  • Have a look at the documentation for strtok, e.g.: http://www.cplusplus.com/reference/cstring/strtok/

    Only the first call expects the buffer. Subsequent calls should pass a null-pointer to retrieve the following token.