(PECL mongo >=0.9.2)
MongoGridFS::storeBytes — Stores a string of bytes in the database
$bytes
   [, array $metadata = array()
   [, array $options = array()
  ]] )
bytes
     String of bytes to store.
metadata
     Other metadata fields to include in the file document.
Note:
These fields may also overwrite those that would be created automatically by the driver, as described in the MongoDB core documentation for the » files collection. Some practical use cases for this behavior would be to specify a custom chunkSize or _id for the file.
options
     An array of options for the insert operations executed against the chunks and files collections. See MongoCollection::insert() for documentation on these these options.
Returns the _id of the saved file document. This will be a generated MongoId unless an _id was explicitly specified in the metadata parameter.
Throws MongoGridFSException if there is an error inserting into the chunks or files collections.
Example #1 MongoGridFS::storeBytes() with additional metadata
<?php
$m = new MongoClient();
$gridfs = $m->selectDB('test')->getGridFS();
$bytes = 'abcdefghijklmnopqrstuvwxyz';
$id = $gridfs->storeBytes($bytes, array('_id' => 'alphabet'));
$gridfsFile = $gridfs->get($id);
var_dump($gridfsFile->file);
?>
The above example will output something similar to:
array(7) {
  ["_id"]=>
  string(8) "alphabet"
  ["uploadDate"]=>
  object(MongoDate)#7 (0) {
  }
  ["length"]=>
  int(26)
  ["chunkSize"]=>
  int(262144)
  ["md5"]=>
  string(32) "c3fcd3d76192e4007dfb496cca67e13b"
}