詳解PHP如何讀取大文件

// formatBytes 方法取材于 php.net 文檔
memory_get_peak_usage();
function formatBytes($bytes, $precision = 2) {
    $units = array("b", "kb", "mb", "gb", "tb");
    $bytes = max($bytes, 0);
    $pow = floor(($bytes ? log($bytes) : 0) / log(1024));
    $pow = min($pow, count($units) - 1);
    $bytes /= (1  (10 * $pow));
    return round($bytes, $precision) . " " . $units[$pow];
}

// from memory.php
function formatBytes($bytes, $precision = 2) {
    $units = array("b", "kb", "mb", "gb", "tb");
    $bytes = max($bytes, 0);
    $pow = floor(($bytes ? log($bytes) : 0) / log(1024));
    $pow = min($pow, count($units) - 1);
    $bytes /= (1  (10 * $pow));
    return round($bytes, $precision) . " " . $units[$pow];
}
print formatBytes(memory_get_peak_usage());
// from reading-files-line-by-line-1.php
function readTheFile($path) {
    $lines = [];
    $handle = fopen($path, "r");
    while(!feof($handle)) {
        $lines[] = trim(fgets($handle));
    }
    fclose($handle);
    return $lines;
}
readTheFile("shakespeare.txt");
require "memory.php";

// from reading-files-line-by-line-2.php
function readTheFile($path) {
    $handle = fopen($path, "r");
    while(!feof($handle)) {
        yield trim(fgets($handle));
    }
    fclose($handle);
}
readTheFile("shakespeare.txt");
require "memory.php";

// from reading-files-line-by-line-3.php
$iterator = readTheFile("shakespeare.txt");
$buffer = "";
foreach ($iterator as $iteration) {
    preg_match("/\n{3}/", $buffer, $matches);
    if (count($matches)) {
        print ".";
        $buffer = "";
    } else {
        $buffer .= $iteration . PHP_EOL;
    }
}
require "memory.php";

// from piping-files-1.php
file_put_contents(
    "piping-files-1.txt", file_get_contents("shakespeare.txt")
);
require "memory.php";

// from piping-files-2.php
$handle1 = fopen("shakespeare.txt", "r");
$handle2 = fopen("piping-files-2.txt", "w");
stream_copy_to_stream($handle1, $handle2);
fclose($handle1);
fclose($handle2);
require "memory.php";

// from piping-files-3.php
file_put_contents(
    "piping-files-3.jpeg", file_get_contents(
        "https://github.com/assertchris/uploads/raw/master/rick.jpg"
    )
);
// ...or write this straight to stdout, if we don't need the memory info
require "memory.php";

// from piping-files-4.php
$handle1 = fopen(
"https://github.com/assertchris/uploads/raw/master/rick.jpg", "r"
);
$handle2 = fopen(
"piping-files-4.jpeg", "w"
);
// ...or write this straight to stdout, if we don't need the memory info
stream_copy_to_stream($handle1, $handle2);
fclose($handle1);
fclose($handle2);
require "memory.php";

$handle1 = fopen(
"https://github.com/assertchris/uploads/raw/master/rick.jpg", "r"
);
$handle2 = fopen(
"php://stdout", "w"
);
stream_copy_to_stream($handle1, $handle2);
fclose($handle1);
fclose($handle2);
// require "memory.php";

// from filters-1.php
$zip = new ZipArchive();
$filename = "filters-1.zip";
$zip->open($filename, ZipArchive::CREATE);
$zip->addFromString("shakespeare.txt", file_get_contents("shakespeare.txt"));
$zip->close();
require "memory.php";

// from filters-2.php
$handle1 = fopen(
"php://filter/zlib.deflate/resource=shakespeare.txt", "r"
);
$handle2 = fopen(
"filters-2.deflated", "w"
);
stream_copy_to_stream($handle1, $handle2);
fclose($handle1);
fclose($handle2);
require "memory.php";

// from filters-2.php
file_get_contents(
    "php://filter/zlib.inflate/resource=filters-2.deflated"
);

// from creating-contexts-1.php
$data = join("", [
    "twitter=assertchris",
]);
$headers = join("\r\n", [
    "Content-type: application/x-www-form-urlencoded",
    "Content-length: " . strlen($data),
]);
$options = [
    "http" => [
        "method" => "POST",
        "header"=> $headers,
        "content" => $data,
    ],
];
$context = stream_content_create($options);
$handle = fopen("https://example.com/register", "r", false, $context);
$response = stream_get_contents($handle);
fclose($handle);

Protocol {
    public resource $context;
    public __construct ( void )
    public __destruct ( void )
    public bool dir_closedir ( void )
    public bool dir_opendir ( string $path , int $options )
    public string dir_readdir ( void )
    public bool dir_rewinddir ( void )
    public bool mkdir ( string $path , int $mode , int $options )
    public bool rename ( string $path_from , string $path_to )
    public bool rmdir ( string $path , int $options )
    public resource stream_cast ( int $cast_as )
    public void stream_close ( void )
    public bool stream_eof ( void )
    public bool stream_flush ( void )
    public bool stream_lock ( int $operation )
    public bool stream_metadata ( string $path , int $option , mixed $value )
    public bool stream_open ( string $path , string $mode , int $options ,
        string $opened_path )
    public string stream_read ( int $count )
    public bool stream_seek ( int $offset , int $whence = SEEK_SET )
    public bool stream_set_option ( int $option , int $arg1 , int $arg2 )
    public array stream_stat ( void )
    public int stream_tell ( void )
    public bool stream_truncate ( int $new_size )
    public int stream_write ( string $data )
    public bool unlink ( string $path )
    public array url_stat ( string $path , int $flags )
}

if (in_array("highlight-names", stream_get_wrappers())) {
    stream_wrapper_unregister("highlight-names");
}
stream_wrapper_register("highlight-names", "HighlightNamesProtocol");
$highlighted = file_get_contents("highlight-names://story.txt");

Filter {
    public $filtername;
    public $params
    public int filter ( resource $in , resource $out , int $consumed ,
        bool $closing )
    public void onClose ( void )
    public bool onCreate ( void )
}

$handle = fopen("story.txt", "w+");
stream_filter_append($handle, "highlight-names", STREAM_FILTER_READ);