PHP exec() as Background Process (Windows Wampserver Environment)-ThrowExceptions

Exception or error:

I’m trying to setup a php trigger file that will set off a background process. (see this question)

I’m doing this on a Windows Wampserver environment.

So for example I have trigger.php that runs the exec function that calls for my backgroundProcess.php to be parsed and executed.

However the problem is that my trigger.php file is waiting for the exec() command to finish running backgroundProcess.php before it stops. The background process runs for about 20-30 seconds, and trigger.php is waiting all that time until backgroundProcess.php has fully finished.

Is that making sense? Here is the trigger.php file that runs the exec() command

exec('C:\wamp\bin\php\php'.phpversion().'\php.exe -f C:\path\to\backgroundProcess.php > C:\wamp\bin\php\php'.phpversion().'\dev\null &');

Basically, I’m wanting trigger.php to just trigger off the backgroundProcess and not wait around for it to finish.


EDIT

Problem solved with the following command:

$WshShell = new COM("WScript.Shell");
$oExec = $WshShell->Run("C:\wamp\bin\php\phpVERSIONNUMBER\php-win.exe -f C:/wamp/www/path/to/backgroundProcess.php", 0, false);
How to solve:

Problem solved with the following command:

$WshShell = new COM("WScript.Shell");
$oExec = $WshShell->Run("C:\wamp\bin\php\phpVERSIONNUMBER\php-win.exe -f C:/wamp/www/path/to/backgroundProcess.php", 0, false);

Answer:

Tried to achieve the same on a Windows 2000 server with PHP 5.2.8.

None of the solutions worked for me. PHP kept waiting for the response.

Found the solution to be :

$cmd = "E:\PHP_folder_path\php.exe E:\some_folder_path\backgroundProcess.php";
pclose(popen("start /B ". $cmd, "a"));  // mode = "a" since I had some logs to edit

ps :
Posting the same reply to the other thread (PHP on a windows machine; Start process in background) since these 2 links helped me a lot in doing some research on this.

Answer:

From the manual : http://www.php.net/manual/en/function.exec.php

Note:

If a program is started with this
function, in order for it to continue
running in the background, the output
of the program must be redirected to a
file or another output stream. Failing
to do so will cause PHP to hang until
the execution of the program ends.

And a similar question I answered : Call another PHP script and return control to user before the other script completes

Answer:

You may need to change your implementation approach. Having to wait for such a long time would be an annoyance for the user of your app and fatal for the entire app.

For such tasks, it’s usually better to queue the task, ideally on database, and process them periodically. There are chron jobs on Linux based systems. In Windows, you can use a scheduler to launch the backgroundProcess.php.

Answer:

It may well be that when using the exec() in a windows environment that redirection is to NUL:. /dev/null is a *nix null file.

Answer:

In addition to Rohit’s answer above, I edited his solution to work on Windows 10 PHP 7.0.3:

pclose(popen("start /B ". $cmd, "w"));

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