进程的退出状态大小为 8 位.无法通过正常方式返回更大的退出状态.如果您想输出一个大于 255 的数字，例如，您可以使用 write 系统调用将其打印到 stdout(文件描述符 1).

The exit status of a process is 8 bits in size. It is not possible to return a larger exit status by normal means. If you want to output a number larger than 255, you could for example print it to stdout (file descriptor 1) with a write system call.