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Home Backend Development PHP Tutorial 为什么crontab -e不能执行fwrite写入文件?蹦溃了。

为什么crontab -e不能执行fwrite写入文件?蹦溃了。

Jun 23, 2016 pm 02:05 PM

function Write_FileFun_new($filename,$filedir, $htmldata = '') {	if(!is_dir($filedir)) {		mkdir($filedir, 0777);	}	$htmlfile = $filedir.$filename;	if($fp = fopen($htmlfile, 'wbt')) {		fwrite($fp,$htmldata);		fclose($fp);	} else {		echo "<center><p>Can not write to files, please check directory $htmldir.</p></center>";		exit;	}}$testnum_temp="<?php \$testnum = ".(intval($testnum)+1)."; ?>";Write_FileFun_new("test.php","inc/", $testnum_temp);
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用浏览器运行页面是正常写入的,
在crontab -e中设置定时每分钟执行一次没有写入文件,crontab -e定时执行是正常,可以每分钟执行一次。
为什么会这样,就差这一个地方了,其它程序都正常执行,就差这个不能写入。为什么啊?


回复讨论(解决方案)

test.php里面的内容一直是,值是1没有变过,就是没有自动加1后写入test.php文件。

inc/ 是相对路径
请先弄清楚是相对谁的

crontab -e的设定是:
*/1 * * * * /usr/bin/php /var/www/html/write.php

inc/ 是/var/www/html/inc
test.php是在/var/www/html/inc/test.php

我在浏览器运行write.php是成功写入的啊……

Write_FileFun_new("test.php","/var/www/html/inc/", $testnum_temp);
改用绝对路径也不行啊,这个有没有权限要求的啊?test.php是设为777的

看看日志,有什么警告信息吗?

日记没警告啊,显示的是:
Apr 8 02:59:01 localhost CROND[25675]: (root) CMD (/usr/bin/php /var/www/html/write.php)

你把crontab里面的命令直接在命令行运行一下看看什么反应

请问命令行怎么写?直接打这个吗:*/1 * * * * /usr/bin/php /var/www/html/write.php

写一个sh,处理好权限 在这个文件里调用/usr/bin/php /var/www/html/write.php 最后在crontab 使用root 身份调用..

既然 web 方式下可以成功,那么 crontab 中也应该成功
差异的产生,可能与你的目录创建和文件打开方式有关
一般web方式下是以apache的模块方式运行的,而crontab中是以 cli 方式运行的
两者使用了不同的主控文件,而文件操作这种基础函数理应放在主控文件中,因为他自己也要用

极有可能是 cli 方式下的 fopen 不能正确处理只在window中才有效的 t 模式,而导致失败
我想你在控制台中运行 /usr/bin/php /var/www/html/write.php 应该是可以看到错误信息的

手册中说
Note: 
再一次,为移植性考虑,强烈建议你重写那些依赖于 't' 模式的代码使其使用正确的行结束符并改成 'b' 模式。

PHP Notice:  Undefined variable: testnum in /var/www/html/write.php on line 28

命令行运行出错,
好象找不到变量testnum,这个变量是在write.php里的include_once('inc/test.php');
也就是上面的要写入的文件内容$testnum_temp="";
初始test.php里面已经有内容
为什么会找不到这个变量?

我晕,现在可以了,谢谢,
原来是include_once('inc/test.php');的问题,不知道为什么用相对路径会不行(浏览器运行是正常的),路径结构又没错。
改成include_once('/var/www/html/inc/test.php');就正常了。

不是说了吗? 相对路径 要先弄清楚是相对谁的

谢谢,没想到包含文件的路径。

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