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<?php
 // Benchmark to measure throughput performance piping an input stream to an output stream.
 // This allows you to get an idea of how fast stream processing with PHP can be
 // and also to play around with differnt types of input and output streams.
 //
 // This example accepts a number of parameters to control the timeout (-t 1),
 // the input file (-i /dev/zero) and the output file (-o /dev/null).
 //
 // $ php examples/91-benchmark-throughput.php
 // $ php examples/91-benchmark-throughput.php -t 10 -o zero.bin
 // $ php examples/91-benchmark-throughput.php -t 60 -i zero.bin
 
 require __DIR__ . '/../vendor/autoload.php';
 
 if (DIRECTORY_SEPARATOR === '\\') {
 fwrite(STDERR, 'Non-blocking console I/O not supported on Microsoft Windows' . PHP_EOL);
 exit(1);
 }
 
 $args = getopt('i:o:t:');
 $if = isset($args['i']) ? $args['i'] : '/dev/zero';
 $of = isset($args['o']) ? $args['o'] : '/dev/null';
 $t  = isset($args['t']) ? $args['t'] : 1;
 
 // passing file descriptors requires mapping paths (https://bugs.php.net/bug.php?id=53465)
 $if = str_replace('/dev/fd/', 'php://fd/', $if);
 $of = str_replace('/dev/fd/', 'php://fd/', $of);
 
 $loop = new React\EventLoop\StreamSelectLoop();
 
 // setup information stream
 $info = new React\Stream\WritableResourceStream(STDERR, $loop);
 if (extension_loaded('xdebug')) {
 $info->write('NOTICE: The "xdebug" extension is loaded, this has a major impact on performance.' . PHP_EOL);
 }
 $info->write('piping from ' . $if . ' to ' . $of . ' (for max ' . $t . ' second(s)) ...'. PHP_EOL);
 
 // setup input and output streams and pipe inbetween
 $fh = fopen($if, 'r');
 $in = new React\Stream\ReadableResourceStream($fh, $loop);
 $out = new React\Stream\WritableResourceStream(fopen($of, 'w'), $loop);
 $in->pipe($out);
 
 // stop input stream in $t seconds
 $start = microtime(true);
 $timeout = $loop->addTimer($t, function () use ($in, &$bytes) {
 $in->close();
 });
 
 // print stream position once stream closes
 $in->on('close', function () use ($fh, $start, $loop, $timeout, $info) {
 $t = microtime(true) - $start;
 $loop->cancelTimer($timeout);
 
 $bytes = ftell($fh);
 
 $info->write('read ' . $bytes . ' byte(s) in ' . round($t, 3) . ' second(s) => ' . round($bytes / 1024 / 1024 / $t, 1) . ' MiB/s' . PHP_EOL);
 $info->write('peak memory usage of ' . round(memory_get_peak_usage(true) / 1024 / 1024, 1) . ' MiB' . PHP_EOL);
 });
 
 $loop->run();
 
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