Altering message text

If an application that uses WTO needs to alter the same message or numerous messages repetitively, using the TEXT parameter on the WTO macro may be useful. You can alter the message or messages in one of two ways:

If you issue 3 different messages, all with identical parameters other than TEXT, you can create a list form of the macro, move the text into the list form, then execute the macro. Using the TEXT parameter you can use the standard form of the macro, and specify the address of the message text. By reducing the number of list and execute forms of the WTO macro in your code, you reduce the storage requirements for your program.
If you need to modify a parameter in message text, using the TEXT parameter enables you to modify the parameter in the storage that you define in your program to contain the message text, rather than modify the WTO parameter list.

Using the TEXT parameter on WTO can reduce your program's storage requirements because of fewer lines of code or fewer list forms of the WTO macro.

To use the WTOR macro, code the message exactly as designated in the single-line WTO macro. (The WTOR macro cannot be used to pass multiple-line messages.) When the message is written, the system adds a message identifier before the message to associate the reply with the message. The system also inserts an indicator as the first character of all WTOR messages, thereby informing the operator that immediate action is required. You must, however, indicate the response desired. In addition, you must supply the address of the area in which the system is to place the reply, and you must indicate the maximum length of the expected reply. The length of the reply may not be zero. You also supply the address of an event control block which the system posts after the reply has been placed, left-adjusted, in your designated area.

You can also supply a command and response token, or CART, with any message. You may have received a CART as input in cases where you issued a message in response to a command. In these cases, you should specify this CART on any messages you issue. Using the CART guarantees that these messages are associated with the command.

A sample WTOR macro is shown in Figure 1. The reply is not necessarily available at the address you specified until the specified ECB has been posted.

Figure 1. Writing to the Operator With a Reply

          .
          .
          XC     ECBAD,ECBAD          Clear ECB
          WTOR   'STANDARD OPERATING CONDITIONS?  REPLY YES OR NO',
                 REPLY,3,ECBAD,ROUTCDE=(1,15)
          WAIT   ECB=ECBAD
          .
          .
ECBAD     DC     F'0'                 Event control block
REPLY     DC     C'bbb'               Answer area

When a WTOR macro is issued, any console receiving the message has the authority to reply. The first reply received by the system is returned to the issuer of the WTOR, providing the syntax of the reply is correct. If the syntax of the reply is not correct, another reply is accepted. The WTOR is satisfied when the system moves the reply into the issuer's reply area and posts the event control block. Each console that received the original WTOR also receives the accepted reply unless it is a security message. A security message is a WTO or WTOR message with routing code 9. No console receives the accepted reply to a security message. A console with master authority may answer any WTOR, even if it did not receive the original message.