How to check if php://input is set?

Question

I need to check if php://input exists/isset. Does it work with php isset() ? What is the proper way to check it?

Answer 1

it returns true if variable exist and its not null

$foo = 'bar';
var_dump(isset($foo));        -> true

$baz = null;
var_dump(isset($baz));        -> false

var_dump(isset($undefined));  -> false