Bug #65650 [Opn]: Using proc_open with file handles fails on large buffers

Edit report at https://bugs.php.net/bug.php?id=65650&edit=1 ID: 65650 User updated by: imprec at gmail dot com Reported by: imprec at gmail dot com Summary: Using proc_open with file handles fails on large buffers Status: Open Type: Bug Package: Program Execution Operating System: Irrelevant PHP Version: 5.4.19 Block user comment: N Private report: N New Comment: Update email Previous Comments: ------------------------------------------------------------------------ [2013-09-10 15:04:25] imprec at gmail dot com Description: ------------ When using proc_open with file handles instead of pipes (required on Windows, because of bug https://bugs.php.net/bug.php?id=51800), when reading large outputs, the result might not retrieve what's expected. The problem has been mentioned when compiling large sass files to stdout on windows. The output may sometimes be different than the actual output you can get running the command in console. The provided script fails 3 times on 5 on windows environment. Nearly everytime on OSX. Test script: --------------- <?php error_reporting(E_ALL); $cmd = sprintf('php -r %s', escapeshellarg('fwrite(STDOUT, $in = file_get_contents(\'php://stdin\')); fwrite(STDERR, $in);')); $stdout = tmpfile(); $stderr = tmpfile(); $descriptors = array( array('pipe', 'r'), $stdout, $stderr, ); $handles = array( $stdout, $stderr ); $datastdin = str_repeat('*!', 8192*128); $options = array_merge(array('suppress_errors' => true, 'binary_pipes' => true, 'bypass_shell' => false)); $process = proc_open($cmd, $descriptors, $pipes, getcwd(), array(), $options); fwrite($pipes[0], $datastdin); fclose($pipes[0]); unset($pipes[0]); $read = array(); while ($handles) { $status = proc_get_status($process); if (!$status['running']) { proc_close($process); } $h = $handles; foreach ($h as $offset => $handle) { fseek($handle, isset($read[$offset]) ? strlen($read[$offset]) : 0); if (!isset($read[$offset])) { $read[$offset] = ''; } $read[$offset] .= fread($handle, 8192); if (false === $status['running'] && feof($handle)) { fclose($handle); unset($handles[$offset]); } } } foreach ($read as $r) { assert($r === $datastdin); } Expected result: ---------------- No errors, assertion is good. Actual result: -------------- PHP Warning: assert(): Assertion failed in C:\symfony\src\Symfony\Component\Pro cess\bug.php on line 47 PHP Warning: assert(): Assertion failed in C:\symfony\src\Symfony\Component\Pro cess\bug.php on line 47 ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=65650&edit=1