Subject: Chained 3270 commands

From: "Greg Rickard" <[email-masked]>
Date: Fri, 15 May 1998 16:14:58 -0500

How does a channel-attached TN3270E server signify to its clients that a 3270 command is chained?

For Read Buffer and Read Modified, chained commands begin operation from the current buffer position, as opposed to buffer address 0 for non-chained reads.  The chained Write command can begin operation from the current buffer position as opposed to the current cursor position for the non-chained Write.

These behaviors are described in the 3174 Functional Description, in chapter 2, "3270 Commands, Orders, and Attributes."  Chaining for local attach is described in chapter 5, "Local Operation."

I have a host that wants to set the buffer position with an unchained Write, then issue a chained Read Buffer to read only from the new position to the end of the buffer.

Greg Rickard
Data Interface Systems