Segmentation error when convert string to array of strings in c - c

Question

I want to convert a string to an array of strings and I get an error
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
int main(int argc, char **argv)
{
int count = 0;
char *str = argv[1];
char *token, *last;
char **arr_str = calloc(9999, sizeof(char*));
token = strtok_r(str, " ,", &last);
arr_str[count] = strcpy(calloc(strlen(token), sizeof(char)), token);
while (token != NULL) {
count++;
token = strtok_r(NULL, " ", &last);
arr_str[count] = strcpy(calloc(strlen(token), sizeof(char)), token);
printf("%s", arr_str[count - 1]);
}
printf("------------");
while(arr_str[count])
printf("%s", arr_str[count--]);
exit (0);
}
how to allocate memory for a string and make a pointer to it from an array?

Answer 1

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
int main(int argc, char **argv)
{
/* always check argument count */
if(argc < 2) {
printf("Not enough arguments given\n");
return 1;
}
int count = 0;
char *str = malloc(strlen(argv[1] + 5));
memcpy(str, argv[1], strlen(argv[1]));
char *token, *last;
char **arr_str = calloc(9999, sizeof(char*));
token = strtok_r(str, " ,", &last);
while ((token = strtok_r(NULL, " ", &last)) != NULL) {
count++;
/* sizeof(char) is always 1 and is redundant unless you are on
a obscure platform that it returns other than 1
which shouldnt exist in modern world
*/
arr_str[count] = malloc(strlen(token) + 1);
strcpy(arr_str[count], token);
}
printf("------------");
while(arr_str[count])
printf("%s", arr_str[count--]);
exit (0);
}
strtok is destructive meaning it edits strings it encounters, it tried to edit argv which resulted in a segmentation error.
I also edited code to follow better practices and edited formatting.
You need memory for elements of the arr_str.
calloc(9999) while not great if this not going to end up in a serious application it's not a issue.
sizeof(char) should always return 1 on a normal modern system unless you are on extremely obscure system
Use puts(char* s) if you don't need string formatting.
You should do input validation.