include和require的区别，其实两者没有太大的区别，如果要包含的文件不存在，include提示notice，然后继续执行下面的语句，require提示致命错误并且退出。
根据测试，win32平台下它们都是先包含后执行，所以被包含文件里最好不要再有include或require语句，这样会造成目录混乱。
或许*nux下情况不同，暂时还没测试。如果一个文件不想被包含多次可以使用include_once或require_once## 读取，写入文档数据：
<span> 1</span> <span>function</span> r(<span>$file_name</span><span>) {
</span><span> 2</span> <span>$filenum</span>=@<span>fopen</span>(<span>$file_name</span>,"r"<span>);
</span><span> 3</span> @<span>flock</span>(<span>$filenum</span>,<span>LOCK_SH);
</span><span> 4</span> <span>$file_data</span>=@<span>fread</span>(<span>$filenum</span>,<span>filesize</span>(<span>$file_name</span><span>));
</span><span> 5</span> @<span>fclose</span>(<span>$filenum</span><span>);
</span><span> 6</span> <span>return</span> <span>$file_data</span><span>;
</span><span> 7</span> <span>}
</span><span> 8</span> <span>function</span> w(<span>$file_name</span>,<span>$data</span>,<span>$method</span>="w"<span>){
</span><span> 9</span> <span>$filenum</span>=@<span>fopen</span>(<span>$file_name</span>,<span>$method</span><span>);
</span><span>10</span> <span>flock</span>(<span>$filenum</span>,<span>LOCK_EX);
</span><span>11</span> <span>$file_data</span>=<span>fwrite</span>(<span>$filenum</span>,<span>$data</span><span>);
</span><span>12</span> <span>fclose</span>(<span>$filenum</span><span>);
</span><span>13</span> <span>return</span> <span>$file_data</span><span>;
</span><span>14</span> }
