Add documentation for examples

Author: clue

examples/benchmark-throughput.php

@@ -1,7 +1,23 @@
 <?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/benchmark-throughput.php
+// $ php examples/benchmark-throughput.php -t 10 -o zero.bin
+// $ php examples/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';

examples/cat.php

@@ -1,11 +1,24 @@
 <?php
 
+// Simple example piping everything from STDIN to STDOUT.
+// This allows you to output everything you type on your keyboard or to redirect
+// the pipes to show contents of files and other streams.
+//
+// $ php examples/cat.php
+// $ php examples/cat.php < README.md
+// $ echo hello | php examples/cat.php
+
 use React\EventLoop\Factory;
 use React\Stream\ReadableResourceStream;
 use React\Stream\WritableResourceStream;
 
 require __DIR__ . '/../vendor/autoload.php';
 
+if (DIRECTORY_SEPARATOR === '\\') {
+    fwrite(STDERR, 'Non-blocking console I/O not supported on Microsoft Windows' . PHP_EOL);
+    exit(1);
+}
+
 $loop = Factory::create();
 
 $stdout = new WritableResourceStream(STDOUT, $loop);