-char **strv_env_merge(unsigned n_lists, ...);
-char **strv_env_delete(char **x, unsigned n_lists, ...);
-
-char **strv_env_set(char **x, const char *p);
-char **strv_env_unset(char **l, const char *p);
-
-char *strv_env_get_with_length(char **l, const char *name, size_t k);
-char *strv_env_get(char **x, const char *n);
-
-char **strv_env_clean(char **l);
-