How to get the size of a temp stream in PHP?

Question

It seems like this ought to be really obvious, but I can't seem to find the answer anywhere. Assuming I create a stream using php://temp, how do I get the length of the data written?

$stream = fopen('php://temp', 'w+');
// ... do some processing here using fwrite, stream_copy_to_stream, stream_filter_append, etc ...
$num_bytes_in_stream = // What goes here? 

Answer 1

php://temp uses a temporary file. The file is empty as long as nothing has been written. fopen expects at least 2 parameters. Mode "w+" can also be used in this case.

$stream = fopen('php://temp','r+');
var_dump(fstat($stream)['size']);  //int(0)

$r = fputs($stream,'1234');
var_dump(fstat($stream)['size']);  //int(4)

rewind($stream);
$str = fgets($stream,'1234');
var_dump($str, fstat($stream)['size']);  //string(4) "1234" int(4)

Try self on https://3v4l.org/Hsodg

Answer 2

You can use strlen to get the number of bytes.

$stream = fopen('php://temp','r');
$content = stream_get_contents($stream);
$num_bytes_in_stream = strlen($content);

check this question: What the correct way to get size of binary data in php?