int unit_write_drop_in_format(Unit *u, UnitSetPropertiesMode mode, const char *name, const char *format, ...) {
        _cleanup_free_ char *p = NULL;
        va_list ap;
        int r;

        assert(u);
        assert(name);
        assert(format);

        if (!(mode & (UNIT_PERSISTENT|UNIT_RUNTIME)))
                return 0;

        va_start(ap, format);
        r = vasprintf(&p, format, ap);
        va_end(ap);

        if (r < 0)
                return -ENOMEM;

        return unit_write_drop_in(u, mode, name, p);
}
int unit_write_drop_in_format(Unit *u, UnitSetPropertiesMode mode, const char *name, const char *format, ...) {
        _cleanup_free_ char *p = NULL;
        va_list ap;
        int r;

        assert(u);
        assert(name);
        assert(format);

        if (!(mode & (UNIT_PERSISTENT|UNIT_RUNTIME)))
                return 0;

        va_start(ap, format);
        r = vasprintf(&p, format, ap);
        va_end(ap);

        if (r < 0)
                return -ENOMEM;

        return unit_write_drop_in(u, mode, name, p);
}