Continue processing after closing connection [duplicate]

Answer 1

As far as I know, unless you're running FastCGI, you can't drop the connection and continue execution (unless you got Endophage's answer to work, which I failed). So you can:

1. Use cron or anything like that to schedule this kind of tasks
2. Use a child process to finish the job

But it gets worse. Even if you spawn a child process with proc_open(), PHP will wait for it to finish before closing connection, even after calling exit(), die(), some_undefined_function_causing_fatal_error(). The only workaround I found is to spawn a child process that itself spawns a child process, like this:

function doInBackground ($_variables, $_code)
{
    proc_open (
        'php -r ' .     
            escapeshellarg ("if (pcntl_fork() === 0) { extract (unserialize (\$argv [1])); $_code }") .
            ' ' . escapeshellarg (serialize ($_variables)),
        array(), $pipes 
    );
}

$message = 'Hello world!';
$filename = tempnam (sys_get_temp_dir(), 'php_test_workaround');
$delay = 10;

doInBackground (compact ('message', 'filename', 'delay'), <<< 'THE_NOWDOC_STRING'
    // Your actual code goes here:
    sleep ($delay);
    file_put_contents ($filename, $message);
THE_NOWDOC_STRING
);

Answer 2

If you are doing this to cache content, you may instead want to consider using an existing caching solution such as memcached.

Answer 3

If running under fastcgi you can use the very nifty:

fastcgi_finish_request();

http://php.net/manual/en/function.fastcgi-finish-request.php

More detailed information is available in a duplicate answer.

Answer 4

I finally found a solution (thanks to Google, I just had to keep trying different combinations of search terms). Thanks to the comment from arr1 on this page (it's about two thirds of the way down the page).

<?php
ob_end_clean();
header("Connection: close");
ignore_user_abort(true);
ob_start();
echo 'Text the user will see';
$size = ob_get_length();
header("Content-Length: $size");
ob_end_flush(); // All output buffers must be flushed here
flush();        // Force output to client
// Do processing here 
sleep(30);
echo('Text user will never see');

I have yet to actually test this but, in short, you send two headers: one that tells the browser exactly how much data to expect then one to tell the browser to close the connection (which it will only do after receiving the expected amount of content). I haven't tested this yet.

Answer 5

You can do that by setting time limit to unlimited and ignoring connection

<?php
ignore_user_abort(true);
set_time_limit(0);

see also: http://www.php.net/manual/en/features.connection-handling.php

Answer 6

PHP doesn't have such persistence (by default). The only way I can think of is run cron jobs to pre-fill the cache.