php实现定时创办指定大小文件脚本
php实现定时创建指定大小文件脚本
公司业务主要做数据备份（支持文件增量备份），因此在测试时，需要定时生成新文件，测试业务运作是否正常。
将以下脚本文件加入crontab，即可实现定时生成新文件。脚本的原理主要是使用dd指令创建指定大小的文件。
<?php $timestamp = time(); $id = uniqid(); $filename = "/tmp/{$timestamp}.img"; $cmd = "dd if=/dev/zero of=$filename bs=4m count=5; echo $id >> {$filename}"; exec($cmd, $ret, $output);?>
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