Callback function invoked after the non-DATA frame |frame| is not sent because of the error. The error is indicated by the |error_code|, which is one of the values defined in ErrorCode.
If this callback returns false, it is treated as fatal error and Session.recv and Session.send functions immediately return ErrorCode.CALLBACK_FAILURE.
See Implementation
Callback function invoked after the non-DATA frame |frame| is not sent because of the error. The error is indicated by the |error_code|, which is one of the values defined in ErrorCode.
If this callback returns false, it is treated as fatal error and Session.recv and Session.send functions immediately return ErrorCode.CALLBACK_FAILURE.