在CentOS或RHEL下,/tmp和/var/tmp 这两个文件夹下的近期没被使用过的文件都会被清掉。
具体请看参考资料
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CentOS / RHEL 6,7 : Why the files in /tmp directory gets deleted periodically
https://www.thegeekdiary.com/centos-rhel-67-why-the-files-in-tmp-directory-gets-deleted-periodically/