C - extract integer between two comma from string

Question

I have a char array containing bicho,25,25-04-2000. I want to extract bicho and put it in a variable and the same goes for 25 and 25-04-2000.

I tried strtok() and sscanf, but no luck at all.

here is my method that i used:

fp = fopen(fn,"r");
while(!feof(fp)){
  fgets(data, 255,fp);
  puts(data);
  pch = strtok (data,",");
  while (pch != NULL)
  {
    printf ("%s\n",pch);
    pch = strtok (NULL, ",");
  }
}

I want to store each value in separate variable not print it.

http://stackoverflow.com/questions/15822660/how-to-parse-a-string-separated-by-commas — ROMANIA_engineer, Jan 09 '16 at 16:45
@rootkea here is my code, fp = fopen(fn,"r"); while(!feof(fp)){ fgets(data, 255,fp); puts(data); pch = strtok (data,","); while (pch != NULL) { printf ("%s\n",pch); pch = strtok (NULL, ","); } } — Hachemi Hamadi, Jan 09 '16 at 16:50
@engineer yes i know this method but i want to store each one in separate variable so i can work with it later. — Hachemi Hamadi, Jan 09 '16 at 16:52
http://port70.net/~nsz/c/c11/n1570.html#7.21.10.2. For details just search a bit here! (3 exclamation marks don't change facts) — too honest for this site, Jan 09 '16 at 17:55

David C. Rankin · Answer 1 · 2016-01-09T17:52:13.780

Your use of feof is not necessary. You can use fgets as the loop condition. Then it is just a matter of storing the strings in an array. You can then numerically convert your number with strtol or atoi (if needed). For example, you could do something like:

#define MAXL 10
#define MAXC 32

char array[MAXL][MAXC] = {{0}};
size_t index = 0;

if (!(fp = fopen (fn, "r"))) {
    fprintf (stderr, "error: file open faied '%s'.\n", fn);
    return 1;
}

while (fgets (data, 255,fp)) 
{
    char *p = data;
    if ((p = strtok (data, ","))) {
        size_t plen = strlen (p);
        if (plen + 1 < MAXC)
            strncpy (array[index++], p, plen + 1);
        else
            fprintf (stderr, "error: string exceeded MAXC\n");

        while (index < MAXL && (p = strtok (NULL, ",\n")) != NULL)
        {
            plen = strlen (p);
            if (plen + 1 < MAXC)
                strncpy (array[index++], p, plen + 1);
            else
                fprintf (stderr, "error: string exceeded MAXC\n");
        }
    }
}

Using a for Loop

You can do the same thing with a for loop a bit more efficiently:

while (fgets (data, 255,fp) 
{
    char *p = data;
    for (p = strtok (data, ","); index < MAXL && p; p = strtok (NULL, ",\n"))
    {
        size_t plen = strlen (p);
        if (plen + 1 < MAXC)
            strncpy (array[index++], p, plen + 1);
        else
            fprintf (stderr, "error: string exceeded MAXC\n");    
    }
}

note: by confirming the length plen before you copy to your array, you can insure your strings are nul-terminated. Let me know if you have further questions.

C - extract integer between two comma from string

1 Answers1