Let's parse.

implementations/C/.gitignore

@@ -1 +1,2 @@
 joy
+parser

implementations/C/parser.c

@@ -0,0 +1,23 @@
+#include <stddef.h>
+#include <stdio.h>
+#include <string.h>
+
+const char *text = "hi there friend";
+/*                  01234567890123456789
+                      ^     ^
+*/
+
+int
+main(void)
+{
+	char *rest;
+	ptrdiff_t diff;
+
+	rest = strpbrk(text, " []");
+	while (NULL != rest) {
+		diff = rest - text;
+                text = rest;
+                printf("%ld\n", diff);
+                rest = strpbrk(++rest, " []");
+	}
+}