Customizing messages

VTAM® provides an extensive set of messages that provide information to a terminal operator, to a program operator, or to a VTAM operator. You can redefine any of these messages by coding a USSMSG macroinstruction for each message to be redefined. These USSMSG macroinstructions are included in a user-defined USS table that is associated with the terminal, a program operator application, or the system console (for messages to the VTAM operator).

Using the USSMSG macroinstruction, you can change the message text and suppression class of any message.

Note:

For information on changing message characteristics, see z/OS Communications Server: SNA Messages.
For more information on how you can use the MVS™ Message Service to change the text of USS messages received by terminal users, see z/OS Communications Server: SNA Network Implementation Guide.
Because program operator applications depend on VTAM messages, changes to the operator messages could disrupt the functioning of a program operator applications.

A message might be only partially defined in a USS table. This allows options on messages to be received from a USS table that is next in the search order hierarchy. See Order of USS table use for more information on the search order for USS tables.

More than one message can be defined using a single USSMSG macroinstruction. If more than one message ID is specified, all of the corresponding messages are changed by the operands specified with this macroinstruction.

The USSMSGxx messages have VTAM equivalents defined in the IBM®-supplied USS tables. For example, ISTINCNO specifies

USSMSG MSG=(IST455I,11)

to define VTAM message IST455I and USSMSG11. These messages can be redefined using a single USSMSG macroinstruction.

Table 1 shows the VTAM message equivalent of USSMSG00 to USSMSG14.

Table 1. USS messages and VTAM message equivalents
USS message number	VTAM operator message
0	IST457I
1	IST450I
2	IST451I
3	IST452I
4	IST453I
6	IST792I
8	IST454I
11	IST455I
12	IST456I
14	IST458I

Note: Allowing the default USSMSG10 to be sent to a non-SNA printer could cause printer forms to be out of alignment. You can avoid this by coding a separate USSTAB for these printers and coding USSMSG10 in this table as follows:

USSMSG MSG=10,BUFFER=BUF10
BUF10     DC    X'0003F57A19'