TCP connection->send always returns null

[muramidaza]

When sending data to a TCP connection, NULL is always returned. But the message always went to the addressee. Perhaps some settings need to be made?

[walkor]

Sending data is asynchronous, and we cannot predict whether the data will actually be sent to the other party, so we return null which indicates that the data has been written to the application layer send buffer of the connection, waiting to be written to the socket send buffer of the system layer.
https://manual.workerman.net/doc/en/tcp-connection/send.html