The following table summarizes state changes that occur when a data transmission error is encountered.
| return_code | Old state | New state |
|---|---|---|
| cm_program_error_purging | RECEIVE | No change |
| cm_program_error_no_trunc | RECEIVE | No change |
| cm_svc_error_purging | SEND | RECEIVE |
| cm_svc_error_no_trunc | SEND_PENDING | RECEIVE |
If the partner program truncates a logical record, the local program receives notification of the truncation through return_code on the next Receive call.
If a program issues Receive with requested_length set to zero, the call is executed as usual. However, data_received and status_received are not set on the same Receive call. (One exception to this situation is the null record sent over a mapped conversation, described in the next paragraph.)
In a mapped conversation in which data is available from the partner program, data_received is set to CM_INCOMPLETE_DATA_RECEIVED. If a null record is available (send_length in the Send_Data call issued by the partner program is set to zero), data_received is set to CM_COMPLETE_RECORD_RECEIVED with received_length set to zero.
In a basic conversation in which data is available and the fill characteristic is set to CM_FILL_LL, data_received is set to CM_INCOMPLETE_DATA_RECEIVED. If the fill characteristic is set to CM_FILL_BUFFER, data_received is set to CM_DATA_RECEIVED.
The LU does not automatically perform any conversion between EBCDIC and ASCII on the received string of data before putting it in buffer. If necessary, the program can use the CSV CONVERT to translate a string from one character set to the other.