Rockwell Automation 1768-EWEB EtherNet/IP Web Server Module User Manual - Manual (Page 148)

Publication ENET-UM527E-EN-P - October 2006
148 Socket Interface
Read The Read service reads data on a socket. You specify a number of
bytes to receive. The Read service returns the number of bytes
received.
For TCP, the Read service returns when any data is received, up to the
requested number of bytes. If no data is received before the timeout
period, the Read service returns a status of success (0) and a BufLen
of 0. The Read service can return fewer bytes than were requested.
Your application might need to issue multiple Read requests to receive
an entire application message.
For UDP, the Read service completes when a datagram is available.
MSG Configuration Parameters
To call this service, click in the MSG instruction and enter the
values displayed below.
Parameter Value
Service Type Read
Service Code 4d
Class 342
Instance from CreateSocket
Attribute 0