Getting a PHP warning on fgets()

[kevintweber]

I am using child processes to create other child processes.

In the grandchildren processes, in Spork / Fifo.php I am receiving the following PHP warning:
PHP Warning: fgets(): 56 is not a valid stream resource in ... /vendor/kriswallsmith/spork/src/Spork/Fifo.php on line 81

One possible fix is the suppress warnings from that function:
while (false !== $data = @fgets($this->read)) {

I hope this helps.