Create a string array to hold divided tokens from a long string?

Question

I have tried everything I know but I just can't create the array. Every time the terminal shows "Segmentation fault: 11". Please help, thanks!(details in my comments)

Updated: char*load file(int *numberofwords)returns reading from txt file(I made it up just to test how my program works):

Have,a.nice day

Bye.

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


char *loadfile(int *counter) {
    int  i;
    char chr;
    char *data;
    char *junk;
    FILE *GENE;
    GENE = fopen("hw7codex.txt", "r");

    if (GENE == NULL) {
       printf("ERROR - Could not open file.\n");
       return NULL; 
    }


   while (1) {
      fscanf(GENE, "%s", junk);
      (*counter)++;
      if (feof(GENE)) break;
   }

   int wholecounter = 0;
   while (1) {
      fscanf(GENE, "%c", &chr);
      wholecounter++;
     if (feof(GENE)) break;
   }

   data = (char *)calloc(wholecounter, sizeof(char));
      if (data == NULL) {
        printf("ERROR - Could not allocate memory for the file.\n");
        return NULL;
   }

   rewind(GENE);
   i = 0;
   while (1) {
       fscanf(GENE, "%c", &chr);
       data[i++] = chr;
       if (feof(GENE)) break;
   }
   fclose(GENE);

   return data;
}






int main(void){

int wordscount=0;

char *temp;

//temp gets a long string from a txt file(which looks like
//"Have,a.nice day"then divides it to separate words:"Have","a", "nice","day"
temp = strtok(loadfile(&wordscount)," ,.\n"); 

//I want to know how many separate words in this txt file
printf("%s\n", loadfile(&wordscount));  //it prints out 5
printf("%d\n", wordscount);       //it prints out 'Have,a.nice day\nBye'


//I want to create a string array here to hold all those words , but I keep failing
char array[wordscount][40];

int j=0;
while (temp != NULL){
    strcpy(array[j], temp);
    j++;
    temp = strtok (NULL, " ,.\n");
    }


for (j = 0; j < wordscount; j++){
   printf("%s\n", array[j]);
    }

Answer 1

char array[wordscount][40]; is illegal if your compiler doesn't support VLA. You should declare an array of pointers that point to strings, then allocate memory manually:

char** array;
int i;
array = (char**)malloc(wordscount * sizeof(char*)); // 

for ( i = 0; i < wordscount; i++) {
    array[i] = (char*)malloc(40 * sizeof(char)); // make sure the length of every word is less than 40
}; 

EDIT:
if the loadfile() return what you write(don't know how you implement the loadfile(), you should allocate memory for the string in the function), and the wordscount is 5, then here is an example for you which works fine:

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

int main(void){

    int wordscount = 5;

    char *temp;
    char buf[128] = "Have,a.nice day\nBye";

    temp = strtok(buf, " ,.\n"); 

    char** array;
    int i;
    array = (char**)malloc(wordscount * sizeof(char*)); // 

    for ( i = 0; i < wordscount; i++) {
        array[i] = (char*)malloc(40 * sizeof(char)); // make sure the length of every word is less than 40
    }; 

    int j = 0;
    while (temp != NULL){
        strcpy(array[j], temp);
        j++;
        temp = strtok (NULL, " ,.\n");
    }

    for (j = 0; j < wordscount; j++){
        printf("%s\n", array[j]);
    }
}

In your loadfile(), junk is an uninitialized pointer, so this line: fscanf(GENE, "%s", junk); will cause undefined behavior.

Answer 2

You char *loadfile(int *counter) seems buggy because you used while (1) {} for reading file and break the loop by if (feof(GENE)) break; but feof it self buggy see here

Also you missed rewind(GENE); between first two while..loop. Add it.

So you can do as follows

   while (fscanf(GENE, "%s", junk)==1) // The scanf functions return the number of objects read.
   {
      (*counter)++;
   }

similar you apply for other loop.

This is the code error i captured form your loadfile function but still i don't know what you expect from return value of loadfile and what output you want?

Answer 3

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

#define DELIMITER " ,.\n"

const char *LoadFile = "data.txt";

char *loadfile(int *wc){
    FILE *fp = fopen(LoadFile, "r");
    if(!fp){
        perror("fopen");
        return NULL;
    }
    long fsize = 0;

    fseek(fp,0,SEEK_END);
    fsize = ftell(fp);//non portable
    fseek(fp,0,SEEK_SET);//reset stream position!!

    char *buff = malloc(fsize+1);
    if(!buff){
        perror("malloc");
        return NULL;
    }
    size_t rsize = fread(buff, sizeof(char), fsize, fp);
    fclose(fp);
    buff[rsize]='\0';

    int count = 0, pos = 0;//long ?
    while(1){
        int len = 0;
        sscanf(buff + pos, "%*[" DELIMITER "]%n", &len);
        pos += len;
        if(EOF!=sscanf(buff + pos, "%*[^" DELIMITER "]%n", &len)){
            pos +=len;
            ++count;
        } else {
            break;
        }
    }
    *wc = count;
    return buff;
}

int main(void){
    int wordscount=0;
    char *buff, *temp;

    buff = loadfile(&wordscount);
    printf("%d\n", wordscount);  

    char array[wordscount][40];

    temp = strtok(buff, DELIMITER);
    int j;
    for(j = 0; temp != NULL; ++j){
        strcpy(array[j], temp);
        temp = strtok (NULL, DELIMITER);
    }
    free(buff);
    for (j = 0; j < wordscount; j++){
        printf("%s\n", array[j]);
    }
    return 0;
}