Frustrated with strtok? Partition parses strings based on strings instead of characters and doesn't fudge the target string.

partition.c

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

struct view { const char *s; size_t len; };

size_t partition(struct view *result, size_t n,
					const char *str, const char *delim){
	char *startp = (char *)str, *endp;
	size_t l = strlen(delim), i = 0;

	while ((endp = strstr(startp, delim)) && (i < n)){
		size_t diff = endp - startp;
		if (diff){
			(result+i)->s = startp;
 			(result+i++)->len = diff;
		}
		startp = endp + l;
	}

	if ((*startp) && (i < n)){
		(result+i)->s = startp;
		(result+i++)->len = strlen(startp);
	}

	return (i > n) ? n : i;
}

char **instantiate(struct view *result, size_t size){
	int i;
	char **strings = malloc((size+1) * sizeof(char *));
	for (i = 0; i < size; i++){
		strings[i] = malloc(((result+i)->len+1) * sizeof(char));
		strncpy(strings[i], (result+i)->s, (result+i)->len);
		strings[i][(result+i)->len] = '\0';
	}
	strings[size] = NULL;
	return strings;
}

void destroy(char **args){
	int i = 0;
	while (args[i]){
		free(args[i++]);
	} free(args);
}

int main(){
	int i = 0;
	size_t n = 1024, ret = 0;
	char **strings;
	struct view *result = malloc(n * sizeof(struct view));
    
	ret = partition(result, n, "foobarfoobarfoobarfoobar", "foo");
	strings = instantiate(result, ret);

	for (i = 0; i < ret; i++){
		printf("%s\n", strings[i]);
	}

	destroy(strings);

	free(result);
	return 0;
}