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There is no solution for PHP itself to perform scheduled tasks, but it is done with the help of the sleep function. This method requires some configuration in advance, such as the implementation process:
<span ignore_user_abort</span>();<span //</span><span 关掉浏览器,PHP脚本也可以继续执行.</span> <span set_time_limit</span>(0);<span //</span><span 通过set_time_limit(0)可以让程序无限制的执行下去</span> <span $interval</span>=60*30;<span //</span><span 每隔半小时运行</span> <span do</span><span { </span><span //</span><span 这里是你要执行的代码 </span> <span sleep</span>(<span $interval</span>);<span //</span><span 等待5分钟</span> }<span while</span>(<span true</span>);
However, I have some concerns about performance issues with this method, but it is also a temporary method.
The method I recommend is to use scripts to implement it, using the scheduled task mechanism of the OS itself, and using bat scripts on windows. But I haven't tried it on windows. Then I will talk about the implementation in Linux.
If your web server is based on Linux, you can use cron job under Linux to complete it. Taking RedHat5 as an example, we only need logic code to be executed regularly in advance. For example demo.php
<?<span php </span><span echo</span> "Hello"<span ; </span>?>
Then encapsulate php with a shell script and call demo.php in the shell script. The demo.sh code is as follows:
#!/bin/<span bash </span><span #if</span> you php install to /usr/local/php/ /usr/local/php/bin/php /home/xx-user/demo.php
After finishing writing the shell script, make sure it has sufficient permissions for this line, for example:/bin/chmod u+x demo.sh.
Then configure cronjob on linux. cronjob is installed by default on linux. If your task needs to be executed by hour, day, week, or month, then you can directly copy your demo.sh script to
/etc/cron.hourly, /etc/cron.daily, /etc/cron.weekly, /etc/cron.monthly are ok, so you can complete your task. If you want to remove the scheduled task at a certain point in time, just move it to other places from the above folders or delete it directly.
If your script has a special execution time, such as every Tuesday, or the 15th of every month. Then you need to configure your own cron job.
For the special configuration of cron, please refer to: http://www.pantz.org/software/cron/croninfo.html
Here I will run this script every 2 minutes between 12:00 am and 14:00 pm every day, then the configuration is as follows (for example, demo.sh is located in the /tmp directory):
First execute crontab -e in the Linux command line, and then enter the rules into it:
*/<span 2</span> <span 12</span>-<span 14</span> * * * /tmp/demo.<span sh</span>
After completing the input, press the "Esc" key on the keyboard, then enter: wq, and the editing page will exit. Then you can use crontab -l to view the cron job you just edited.
At this point the special cron is completed. For example, if you just used the demo account under Linux to complete the above steps, then there is another simple way to directly edit the /var/spool/cron/demo file, you can directly
Modify your cron job. For example: vi /var/spool/cron/demo
Using the OS to manage your scheduled tasks is very fast, and you don’t have to worry about performance issues unless there are some problems with your script itself. This method is easy to maintain, you can modify the scheduled execution plan, and you can also easily remove and add other scheduled tasks.