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Detailed explanation of how to implement scheduled tasks in PHP_PHP Tutorial

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2016-07-20 11:12:05965browse

This article summarizes some commonly used detailed explanations on how to implement scheduled tasks in PHP, including directly using PHP to operate, and using scheduled tasks of the operating system to operate. Students who need to know more can refer to it.

Each PHP script has a limited execution time, so we need to set the execution time of a script to unlimited through set_time_limit; then use flush() and ob_flush() to clear the server buffer and output the return value of the script at any time . When we execute, every 5 seconds, we will get a line of Hello World

The code is as follows Copy code
 代码如下 复制代码

header("Content-Type: text/plain");
set_time_limit(0);

$infoString = "Hello World" . "n";
while( isset($infoString) )
{
echo $infoString;
flush();
ob_flush();
sleep(5);
}

header("Content-Type: text/plain");
set_time_limit(0);

$infoString = "Hello World" . "n";
while( isset($infoString) )
{
echo $infoString;
flush();
ob_flush();
sleep(5);
}
 代码如下 复制代码

ignore_user_abort(); // 即使Client断开(如关掉浏览器),PHP脚本也可以继续执行.
set_time_limit(0); // 执行时间为无限制,php默认的执行时间是30秒,通过set_time_limit(0)可以让程序无限制的执行下去
$interval=20; // 时间间隔 单位 秒
$key_file="key.txt"; // 配置文件
if (isset($_GET['s']))
{
if ($_GET['s']=="0"){ // 停止工作,但不退出
$s="false";
echo "Function is off";
}
elseif ($_GET['s']=="1"){ // 工作
$s="true";
echo "Function is on";
}
elseif ($_GET['s']=="2"){ // 退出
$s="die";
echo "Function exited";
}
else
die("Err 0:stop working 1:working 2:exit");
$string = "";
  write_inc($key_file,$string,true);
  exit();
}
if(file_exists($key_file)){
  do{
    $mkey = include $key_file;
    if ($mkey=="true"){          // 如果工作
    /////////////////////  工作区间  //////////////////////////////////
      $showtime=date("Y-m-d H:i:s");
      $fp = fopen('func.txt','a');
      fwrite($fp,$showtime."n");
      fclose($fp);
    ///////////////////////////////////////////////////////////////////
    }
    elseif ($mkey=="die"){        // 如果退出
      die("I am dying!");
    }
    sleep($interval);           // 等待$interval分钟
  }while(true);
}
else
  die($key_file." doesn't exist !");
function write_inc($path,$strings,$type=false)
{  
  $path=dirname(__FILE__)."/".$path;
  if ($type==false)
    file_put_contents($path,$strings,FILE_APPEND);
  else
    file_put_contents($path,$strings);
}
?>

Example
The code is as follows Copy code
ignore_user_abort(); // Even if the Client is disconnected (such as closing the browser), the PHP script can continue to execute.
set_time_limit(0); // The execution time is unlimited , the default execution time of PHP is 30 seconds. Through set_time_limit(0), the program can be executed without limit
$interval=20; ; // Configure files
if (isset ($ _ get ['s']))
{
if ($ _get ['s'] == "0") {// Stop stop Work, but don't exit
$s="false";
echo "Function is off";
}
elseif ($_GET['s']=="1" ){ // work
$s="true";
echo "Function is on";
}
elseif ($_GET['s']=="2" ){ // Exit
$s="die";
echo "Function exited";
}
else
die("Err 0:stop working 1: working 2:exit");
$string = "";
write_inc($key_file,$string,true);
exit();
}
if(file_exists($key_file)){
do{
$mkey = include $key_file;
if ($ mkey=="true"){ // If working
////////////////////// Working range /////////// ///////////////////////
          $showtime=date("Y-m-d H:i:s");                   $fp = fopen ('func.txt','a');
fwrite($fp,$showtime."n");
fclose($fp);
/////// ///////////////////////////////////////////////////// //////////
}
elseif ($mkey=="die"){                                                                                                                                                                                                                                         /> }
sleep($interval); // Wait for $interval minutes
}while(true);
}
else
die($key_file." doesn's 't exist !");
function write_inc($path,$strings,$type=false)
{
$path=dirname(__FILE__)."/".$path; if ($type==false)
file_put_contents($path,$strings,FILE_APPEND);
else
file_put_contents($path,$strings);
} ?>

Personally, I feel that executing tasks regularly in PHP is still a bit complicated and difficult to use. Now I will introduce how to implement scheduled tasks in the operating system.

I looked for some methods on the Internet to execute PHP scheduled tasks in Windows, and one of them was very comprehensive, but unfortunately it didn’t pass in my case. In the end, I had to combine the methods of various sects to successfully operate it here.

1. Write a PHP program, named test.php, with the following content:

The code is as follows Copy code
 代码如下 复制代码

 

$fp = fopen("test.txt", "a+");

fwrite($fp, date("Y-m-d H:i:s") . " 成功成功了!n");

fclose($fp);

?>


$fp = fopen("test .txt", "a+");

代码如下 复制代码

D:phpphp.exe -q D:websitetest.php

fwrite($fp, date("Y-m-d H:i:s") . " Success succeeded! n");

fclose($ fp);

?>


The program is written boldly, and you can use any includerequire, no problem
2. Create a new Bat The file is named test.bat and the content is as follows:
The code is as follows Copy code
D:phpphp.exe -q D:websitetest.php
//Change the corresponding directory yourself


3. Create a WINDOWS scheduled task: Start–>Control Panel–>Task Schedule–>Add Task Schedule

Browse Select the bat file above in the folder

Set the time and password (login to WINDOWS)

Save it.

4. over! You can right-click the scheduled task and click "Run" to try



In Linux system

 代码如下 复制代码
# crontab -e
2.00 * * * * /usr/local/bin/php /home/john/myscript.php
/usr/local/bin/php

We can use Linux's Crontab Tools to trigger PHP execution tasks stably and reliably.

The two methods of Crontab are introduced below.


1. Use PHP to execute the script in Crontab
Just like calling a normal shell script in Crontab (specific Crontab usage), use the PHP program to call the PHP script.

Execute myscript.php every hour as follows:
 代码如下 复制代码
1.00 * * * * lynx -dump /myscript.php

1.

The code is as follows Copy code
# crontab -e
 代码如下 复制代码
1.*/5 * * * * /usr/bin/curl -o temp.txt /myscript.php
2.00 * * * * /usr/local/bin/php /home/ john/myscript.php/usr/local/bin/php
is the path of the PHP program. 2. Use URL to execute scripts in Crontab If your PHP script can be triggered by URL, you can use lynx or curl or wget to configure your Crontab. The following example uses Lynx text browser to access a URL to execute a PHP script every hour. Lynx text browser uses conversational mode to open URLs by default. However, as shown below, we use the -dump option on the lynx command line to convert the URL output to standard output.
The code is as follows Copy code
1.00 * * * * lynx -dump /myscript.php
The following example is to use CURL to access the URL to execute every 5 minutes PHP script. Curl displays output on standard output by default. You can also dump the script's output to a temporary file using the "curl -o" option.
The code is as follows Copy code
1.*/5 * * * * /usr/bin/curl -o temp.txt /myscript.php

The following example uses WGET to access the URL to execute a PHP script every 10 minutes. The -q option indicates quiet mode. "-O temp.txt" means the output will be sent to a temporary file.

The code is as follows
 代码如下 复制代码

1.*/10 * * * * /usr/bin/wget -q -O temp.txt /myscript.php

Copy code
1.*/10 * * * * /usr/bin/wget -q -O temp.txt /myscript.php

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This article summarizes some common detailed methods for implementing scheduled tasks in PHP, including directly using PHP To operate, you can also use the operating system's scheduled tasks to operate, there are...
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