$stdout is a global variable that represents the current standard output.
STDOUT is a constant representing standard output and is typically the default value of
STDOUT being a constant, you shouldn’t re-define it, however, you can re-define
$stdout without errors/warnings (re-defining
STDOUT will raise a warning). for example, you can do:
$stdout = STDERR
Same goes for
So, to answer the other part of your question, use the global variables to redirect output, not the constants. Just be careful to change it back further on in your code, re-defining global variables can impact other parts of your application.