Question

I’m trying to use popen to run a php script in the background. However, I need to pass a (fairly large) serialized object.

$cmd = "php background_test.php >log/output.log &";
$fh = popen($cmd, 'w');
fwrite($fh, $data); 
fclose($fh);
//pclose($fh);

Without the ampersand this code executes fine but the parent script will wait until the child is finished running. With the ampersand STDIN gets no data.

Any ideas?

Answer 1

As far as I know there is no way in php to send a process in background and continue to feed its STDIN (but maybe I’m wrong). You have two other choices here:

1. Refactor your background_test.php to get its input from command line and transform your command line in php background_test.php arg1 arg2 ... >log/output.log &
2. If your input is pretty long, write it to a temporary file and then feed the background_test.php script with that file as in the following code

Example for point 2:

<?
$tmp_file = tempnam();
file_put_content($tmp_file, $data);
$cmd = "php background_test.php < $tmp_name > log/output.log &";
exec($cmd);