To read the CSV file in C

read_csv.c

#include <stdio.h>
#include <string.h>
#include <stdlib.h>


void read_csv(int row, int col, char *filename, double **data){
	FILE *file;
	file = fopen(filename, "r");

	int i = 0;
    char line[4098];
	while (fgets(line, 4098, file) && (i < row))
    {
    	// double row[ssParams->nreal + 1];
        char* tmp = strdup(line);

	    int j = 0;
	    const char* tok;
	    for (tok = strtok(line, "\t"); tok && *tok; j++, tok = strtok(NULL, "\t\n"))
	    {
	        data[i][j] = atof(tok);
	        printf("%f\t", data[i][j]);
	    }
	    printf("\n");

        free(tmp);
        i++;
    }
}

int main(int argc, char const *argv[])
{
	/* code */
	if (argc < 3){
		printf("Please specify the CSV file as an input.\n");
		exit(0);
	}

	int row     = atoi(argv[1]);
	int col     = atoi(argv[2]);
	char fname[256];	strcpy(fname, argv[3]);

	double **data;
	data = (double **)malloc(row * sizeof(double *));
	for (int i = 0; i < row; ++i){
		data[i] = (double *)malloc(col * sizeof(double));
	}

	read_csv(row, col, fname, data);

	return 0;
}

where and how do i mention the file name

You need to pass the file name as the command line argument while running the program.
For example
./a.out 500 15 data_file.csv
where a.out is the executable, 500 is the number of rows, 15 is the number of columns and data_file.csv is the file name which is present in the current directory.

This code is reading only one row .

indeed is reading only one row and filling the rest with zeros. Did someone managed to finish the function?

The code it's working fine, but you need to customize it according your csv file. In my case, the values were separeted by ",", so I needed to change the code as follow:

for (tok = strtok(line, ","); tok && *tok; j++, tok = strtok(NULL, ","))

Very helpful program. Thank you !!

Thank you @manoharmukku.
the code is run using linux, right?

I ran it under Windows 10 using gcc

Thank you @manoharmukku.
the code is run using linux, right?

The code can be run in any command line (terminal) which has gcc. It works for Linux, MacOS and Windows.