如果我把一个新的脚本放到/etc/cron.d/系统如何知道把它插入到全局的crontab中？
我是否需要重新启动一个进程来提取？
init是否每分钟运行一次crontab，然后再重新扫描呢？
它使用inotify和看/etc/cron.d ？
找不到任何非常明显的东西，我一直在想
从cron（8）：
Additionally, cron reads the files in /etc/cron.d: it treats the files in /etc/cron.d as in the same way as the /etc/crontab file … cron then wakes up every minute, examining all stored crontabs, checking each com‐ mand to see if it should be run in the current minute. When executing commands, any output is mailed to the owner of the crontab (or to the user named in the MAILTO environment variable in the crontab, if such exists). The children copies of cron running these processes have their name coerced to uppercase, as will be seen in the syslog and ps output. Additionally, cron checks each minute to see if its spool directory's modtime (or the modtime on /etc/crontab) has changed, and if it has, cron will then examine the modtime on all crontabs and reload those which have changed. Thus cron need not be restarted whenever a crontab file is modified. Note that the crontab(1) command updates the modtime of the spool directory whenever it changes a crontab.
另请注意，cron不会“将cron.d的内容插入到全局crontab中” – 这些是独立的：
However, they are independent of /etc/crontab: they do not, for example, inherit environment variable settings from it.