void free_argv(char **argv);
int para_regcomp(regex_t *preg, const char *regex, int cflags);
void freep(void *arg);
+int compute_word_num(const char *buf, const char *delim, int offset);
+char *safe_strdup(const char *src, size_t len);
+char *key_value_copy(const char *src, size_t len, const char *key);