PHP x86 How to get filesize of > 2 GB file without external program?

<?php
  ######################################################################
  # Human size for files smaller or bigger than 2 GB on 32 bit Systems #
  # size.php - 1.1 - 17.01.2012 - Alessandro Marinuzzi - www.alecos.it #
  ######################################################################
  function showsize($file) {
    if (strtoupper(substr(PHP_OS, 0, 3)) == 'WIN') {
      if (class_exists("COM")) {
        $fsobj = new COM('Scripting.FileSystemObject');
        $f = $fsobj->GetFile(realpath($file));
        $file = $f->Size;
      } else {
        $file = trim(exec("for %F in (\"" . $file . "\") do @echo %~zF"));
      }
    } elseif (PHP_OS == 'Darwin') {
      $file = trim(shell_exec("stat -f %z " . escapeshellarg($file)));
    } elseif ((PHP_OS == 'Linux') || (PHP_OS == 'FreeBSD') || (PHP_OS == 'Unix') || (PHP_OS == 'SunOS')) {
      $file = trim(shell_exec("stat -c%s " . escapeshellarg($file)));
    } else {
      $file = filesize($file);
    }
    if ($file < 1024) {
      echo $file . ' Byte';
    } elseif ($file < 1048576) {
      echo round($file / 1024, 2) . ' KB';
    } elseif ($file < 1073741824) {
      echo round($file / 1048576, 2) . ' MB';
    } elseif ($file < 1099511627776) {
      echo round($file / 1073741824, 2) . ' GB';
    } elseif ($file < 1125899906842624) {
      echo round($file / 1099511627776, 2) . ' TB';
    } elseif ($file < 1152921504606846976) {
      echo round($file / 1125899906842624, 2) . ' PB';
    } elseif ($file < 1180591620717411303424) {
      echo round($file / 1152921504606846976, 2) . ' EB';
    } elseif ($file < 1208925819614629174706176) {
      echo round($file / 1180591620717411303424, 2) . ' ZB';
    } else {
      echo round($file / 1208925819614629174706176, 2) . ' YB';
    }
  }
?>

Use as follow:

<?php include("php/size.php"); ?>

And where you want:

<?php showsize("files/VeryBigFile.rar"); ?>

If you want improve it you are welcome!

Here's one possible method:

It first attempts to use a platform-appropriate shell command (Windows shell substitution modifiers or *nix/Mac stat command). If that fails, it tries COM (if on Windows), and finally falls back to filesize().

/*
 * This software may be modified and distributed under the terms
 * of the MIT license.
 */

function filesize64($file)
{
    static $iswin;
    if (!isset($iswin)) {
        $iswin = (strtoupper(substr(PHP_OS, 0, 3)) == 'WIN');
    }

    static $exec_works;
    if (!isset($exec_works)) {
        $exec_works = (function_exists('exec') && !ini_get('safe_mode') && @exec('echo EXEC') == 'EXEC');
    }

    // try a shell command
    if ($exec_works) {
        $cmd = ($iswin) ? "for %F in (\"$file\") do @echo %~zF" : "stat -c%s \"$file\"";
        @exec($cmd, $output);
        if (is_array($output) && ctype_digit($size = trim(implode("\n", $output)))) {
            return $size;
        }
    }

    // try the Windows COM interface
    if ($iswin && class_exists("COM")) {
        try {
            $fsobj = new COM('Scripting.FileSystemObject');
            $f = $fsobj->GetFile( realpath($file) );
            $size = $f->Size;
        } catch (Exception $e) {
            $size = null;
        }
        if (ctype_digit($size)) {
            return $size;
        }
    }

    // if all else fails
    return filesize($file);
}

I've started project called Big File Tools. It is proven to work on Linux, Mac and Windows (even 32-bit variants). It provides byte-precise results even for huge files (>4GB). Internally it uses brick/math - arbitrary-precision arithmetic library.

Install it using composer.

composer install jkuchar/BigFileTools

and use it:

<?php
$file = BigFileTools\BigFileTools::createDefault()->getFile(__FILE__);
echo $file->getSize() . " bytes\n";

Result is BigInteger so you can compute with results

$sizeInBytes = $file->getSize();
$sizeInMegabytes = $sizeInBytes->toBigDecimal()->dividedBy(1024*1024, 2, \Brick\Math\RoundingMode::HALF_DOWN);    
echo "Size is $sizeInMegabytes megabytes\n";

---

Big File Tools internally uses drivers to reliably determine exact file size on all platforms. Here is list of available drivers (updated 2016-02-05)

| Driver           | Time (s) ↓          | Runtime requirements | Platform 
| ---------------  | ------------------- | --------------       | ---------
| CurlDriver       | 0.00045299530029297 | CURL extension       | -
| NativeSeekDriver | 0.00052094459533691 | -                    | -
| ComDriver        | 0.0031449794769287  | COM+.NET extension   | Windows only
| ExecDriver       | 0.042937040328979   | exec() enabled       | Windows, Linux, OS X
| NativeRead       | 2.7670161724091     | -                    | -

You can use BigFileTools with any of these or fastest available is chosen by default (BigFileTools::createDefault())

 use BigFileTools\BigFileTools;
 use BigFileTools\Driver;
 $bigFileTools = new BigFileTools(new Driver\CurlDriver());