为什么ftp_cdup函数会返回false？常见原因和解决办法

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</span><span><span class="hljs-keyword">echo</span></span><span> </span><span><span class="hljs-string">"<h1>为什么ftp_cdup函数会返回false？常见原因和解决办法</h1>"</span></span><span>;

</span><span><span class="hljs-keyword">echo</span></span><span> </span><span><span class="hljs-string">"<p>在使用 PHP 的 FTP 函数时，<code>ftp_cdup