Req->Bug #39507 [Opn->Csd]: concurrent attempts to connect to SMTP relay fail miserably

Edit report at https://bugs.php.net/bug.php?id=39507&edit=1 ID: 39507 Updated by: cmb@php.net Reported by: rherror404 at gmail dot com Summary: concurrent attempts to connect to SMTP relay fail miserably -Status: Open +Status: Closed -Type: Feature/Change Request +Type: Bug -Package: Feature/Change Request +Package: *General Issues Operating System: Windows PHP Version: 5.2.0 -Assigned To: +Assigned To: cmb Block user comment: N Private report: N New Comment: This is fixed[1] as of PHP 7.0.0. [1] <https://github.com/php/php-src/commit/2841aa95db84f3563c94c90f84bf7f47ba159a2d> Previous Comments: ------------------------------------------------------------------------ [2009-07-09 19:39:40] php at shitware dot nl I have a simple test script sending out an e-mail message at exactly the same time. One sends to rob@work.com, other to rob@home.com. 'Sometimes' the two get mixed up completely. This is what I received 'at home': Date: Thu, 09 Jul 2009 17:48:00 +0200 Subject: parallel test From: rob@work.org MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="==Multipart_Boundary_x0a08807ab511e1f5db827a961c83fe3cx" To: rob@work.com --==Multipart_Boundary_x0a08807ab511e1f5db827a961c83fe3cx Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit parallel test --==Multipart_Boundary_x0a08807ab511e1f5db827a961c83fe3cx Content-ID: 91ca2796c5b3542ce33422e15c31414d Content-Type: application/pdf; name="test.pdf" Content-Transfer-Encoding: base64 JVBERi0xLjMNJeLjz9MNCjcxOCAwIG9iag08PC9MaW5lYXJpemVkIDEvTCAxNzA1NzMvTyA3MjAv RSAzMTEzNy9OIDYvVCAxNTYxNjUvSCBbIDkzNCAzMTddPj4NZW5kb2JqDSAgICAgICAgICAgICAg //snip snip -- up until the next 2.5 lines is only part of the attachment //see where the new 'header' starts ... YmoNNzMyIDAgb2JqDTw8L0xlbmd0aCA3NDYvRmlsdGVyL0ZsYXRlRGVjb2RlPj5zdHJlYW0NCkiJ zFdNj9MwEL33V/gPbOoZexxbqiy1aSqBtCdyQwit+DggQBwWiZ/PxB+xs6Vs8fbAwUrsODOTN+/N OLvTeDpJidJ7Lw7HQWx2UkLvpy+b8Z5n2ElyQorp4+YtP1FWSqN57D1InpDate: Thu, 09 Jul 2009 17:48:00 +0200 Subject: parallel test to rob@home.com at 17:48:00 From: rob@work.com MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="==Multipart_Boundary_x0a08807ab511e1f5db827a961c83fe3cx" To: rob@home.com --==Multipart_Boundary_x0a08807ab511e1f5db827a961c83fe3cx Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit parallel test --==Multipart_Boundary_x0a08807ab511e1f5db827a961c83fe3cx Content-ID: 91ca2796c5b3542ce33422e15c31414d Content-Type: application/pdf; name="test.pdf" Content-Transfer-Encoding: base64 JVBERi0xLjMNJeLjz9MNCjcxOCAwIG9iag08PC9MaW5lYXJpemVkIDEvTCAxNzA1NzMvTyA3MjAv RSAzMTEzNy9OIDYvVCAxNTYxNjUvSCBbIDkzNCAzMTddPj4NZW5kb2JqDSAgICAgICAgICAgICAg //snip snip -- full PDF MDAwMDAwMDAwIDY1NTM1IGYNCjAwMDAwMDAwMDAgNjU1MzUgZg0KdHJhaWxlcg0KPDwvU2l6ZSA3 MTg+Pg0Kc3RhcnR4cmVmDQoxMTYNCiUlRU9GDQo= --==Multipart_Boundary_x0a08807ab511e1f5db827a961c83fe3cx-- We have this same problem on a production site (WAMP) where 'sometimes' e-mail messages and/or attachments end up in 'the wrong place'. In short: no, the mail() function is not thread-safe! ------------------------------------------------------------------------ [2007-01-07 05:41:31] rherror404 at gmail dot com > It sounds like SMTP server flood > limiter is being triggered > here. Not a PHP issue. Nice try, but it is a PHP issue, at least under Apache on win32. I only tried sending only just a few messages at a time. My earlier remark about "serious volumes" isn't what this bug report is about, it's about being able to send MORE THAN JUST ONE at a time without it stumbling all over itself. My testing used EXACTLY TWO concurrent attempts. Please re-read my remarks about execution under the Apache WinNT MPM. Is the mail() function thread-safe? ------------------------------------------------------------------------ [2007-01-07 05:01:48] iliaa@php.net Sorry, but your problem does not imply a bug in PHP itself. For a list of more appropriate places to ask for help using PHP, please visit http://www.php.net/support.php as this bug system is not the appropriate forum for asking support questions. Due to the volume of reports we can not explain in detail here why your report is not a bug. The support channels will be able to provide an explanation for you. Thank you for your interest in PHP. It sounds like SMTP server flood limiter is being triggered here. Not a PHP issue. ------------------------------------------------------------------------ [2006-11-20 19:42:15] rherror404 at gmail dot com I have found a work-around (not a fix). Do not rely upon the current mail() (at least under the Apache WinNT MPM) to be of any use for the case where more than one mod_php script is forwarding a message to an SMTP relay host. Have the mod_php script spawn a child process that takes a bit of serialized state via its STDIN and let the new process do the mail() work. See the proc_open() docs. If you have serious volumes of mail to send, either do it from a Linux box or find some other way to do it from your Windows box. Calling mail() under Windows/Apache/PHP for anything close to that (as it stands) is not advisable. ------------------------------------------------------------------------ [2006-11-14 16:14:10] rherror404 at gmail dot com I suspect this may be the same bug mentioned in #31676. My best guess is that this is related to multi-threading. ------------------------------------------------------------------------ The remainder of the comments for this report are too long. To view the rest of the comments, please view the bug report online at https://bugs.php.net/bug.php?id=39507 -- Edit this bug report at https://bugs.php.net/bug.php?id=39507&edit=1