Passing data from a two-dimensional array to a structure - c

Question

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
typedef struct words {
char *mas;
}words;
int main(void) {
FILE *fp=fopen("test.txt", "r");
char str[100];
char arr[100][100];
int k=0;
words_in->mas=malloc(sizeof(char)*sizeof(arr));
char *istr;
printf("\nFile text\n\n");
for (int i = 0; i < 3; i++) {
istr = fgets(str, 100, fp);
printf("%s", istr);
for (char* istr = strtok(str, " .\t\n"); istr; istr = strtok(NULL, " .\t\n")) {
strcpy(arr[k++], istr);
}
}
How do I pass all words written to the two-dimensional array to the structure?
I want my structure to have an array of char pointers, instead of just one pointer. Or a linked list of pointers. Or an array of structs.
And is it possible to somehow dynamically allocate memory for the structure and for arrays?

Answer 1

If you want to prevent two loops and you are ready to sacrifice some memory you can follow this approach
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <string.h>
typedef struct words {
char **mas;
}words;
int main()
{
FILE *fp=fopen("test.txt", "r");
struct stat statbuf;
fstat(fileno(fp), &statbuf);
long f_size = statbuf.st_size;
words words_in;
words_in.mas = (char**) malloc(sizeof(char*) * f_size); // In worst case each byte is one word.
char fbuf[f_size+1]; // In worst case all bytes form one word ;
long word_count = 0;
while(fscanf(fp,"%s", fbuf) == 1) {
words_in.mas[word_count] = strdup(fbuf);
word_count++;
}
for (long i = 0; i < word_count; i++) {
printf("%s\n",words_in.mas[i]);
}
return 0;
}
INPUT 1
Apple
Bat
Cat
OUTPUT 1
Apple
Bat
Cat
INPUT 2
AppleBatCat
OUTPUT 2
AppleBatCat
INPUT 3
Apple Bat Cat
OUTPUT 3
Apple
Bat
Cat