Retrieves the usage count (subscription count) for a specific file stream.
This function checks the current usage count for an open file stream, which represents the number of active subscriptions.
Throws
Thrown if the environment is not a Node.js server.
Throws
Thrown if the file stream does not exist.
Throws
Thrown if the file stream does not provide a counter, indicating it has never been subscribed to.
Throws
Thrown if the file stream to read counter from is not open.
Retrieves the usage count (subscription count) for a specific file stream. This function checks the current usage count for an open file stream, which represents the number of active subscriptions.
Throws
Thrown if the environment is not a Node.js server.
Throws
Thrown if the file stream does not exist.
Throws
Thrown if the file stream does not provide a counter, indicating it has never been subscribed to.
Throws
Thrown if the file stream to read counter from is not open.