stream_copy_to_stream()

(PHP 5, PHP 7)

Copies data from one stream to another

说明

stream_copy_to_stream(resource $source,resource $dest[,int $maxlength=-1[,int $offset= 0]]): int

Makes a copy of up to$maxlengthbytes of data from the current position (or from the$offsetposition, if specified)in$sourceto$dest.If$maxlengthis not specified, all remaining content in$sourcewill be copied.

参数

$source

The source stream

$dest

The destination stream

$maxlength

Maximum bytes to copy

$offset

The offset where to start to copy data

返回值

Returns the total count of bytes copied,或者在失败时返回FALSE.

更新日志

范例

Astream_copy_to_stream()example

<?php
$src = fopen('http://www.example.com', 'r');
$dest1 = fopen('first1k.txt', 'w');
$dest2 = fopen('remainder.txt', 'w');
echo stream_copy_to_stream($src, $dest1, 1024) . " bytes copied to first1k.txt\n";
echo stream_copy_to_stream($src, $dest2) . " bytes copied to remainder.txt\n";
?>

参见

• copy() 拷贝文件

note that this function does not actually use sendfile() on linux systems (at least not in PHP 7.2.12)

stream_copy_to_stream almost copies a stream...
$objInputStream = fopen("php://input", "rb");
$objTempStream = fopen("php://temp", "w+b");
stream_copy_to_stream($objInputStream, $objTempStream);
That code will copy a stream but it will also move the stream pointers to EOF. This is fine if you plan on rewinding the temp stream but good luck rewinding the input stream.
rewind($objTempStream);
rewind($objInputStream);
So as you can see this is stream copy or stream move depending on what kind of stream you are working with, and because there are no peaking functions your effed if you need to read from an input stream in multiple classes that are unrelated.

As stream_copy_to_stream() seems to be quite a memory hog (at least in PHP 5.1.6 64-bit) it may be way more efficient just to copy streams with this simple PHP alternative:
<?php
  function pipe_streams($in, $out)
  {
    $size = 0;
    while (!feof($in)) $size += fwrite($out,fread($in,8192));
    return $size;
  }
?>