HP 3000 Manuals HP 3000 Manuals
Messages
HP ALLBASE/4GL uses five different types of messages. Each has a
different effect on the application. The five message types are:
Type Description
MESS Message only.
QUERY The user must enter a response.
WARN Warning only, message plus terminal bell.
ERROR The user must take action to continue.
ABORT The application terminates when the user presses
Return.
When you select the type of message to use in your application, you must
decide what should happen in the application after the message is
displayed.
A message telling the user that a record may be modified should be a MESS
type message. It is for information purposes only.
A message to confirm that the user wants to delete a record should be a
QUERY type message. The user must respond to a query message. You can
test the user's response to a query message to determine the subsequent
action taken by the application.
If the user makes an invalid entry, you should use an ERROR type message.
In this case, the user cannot move off the current field without making a
valid entry.
If the field is not crucial, the message could be a WARN type message.
In this case the message is displayed along with a terminal bell sound.
No specific response or action is required from the user.
If the application or the interface to the host operating system detects
a fatal error, you may choose to specify an ABORT message. In this case,
the message text is displayed on the screen, and the application
terminates when the user presses Return.
This application requires the following 8 messages, referred to in the
process and functions you have defined so far.
* This message tells the user that an unexpected file error has
occurred. It is an ERROR type message:
* file_error
* This message tells the user that an appropriate action may be
taken. It is a MESS type message:
* add_prod
* These messages tell the user that an update action has succeeded.
They are MESS type messages:
* prod_add_ok, prod_modify_ok, prod_delete_ok
* These messages are used to tell the user that a selected action
may not be executed, or has failed. They are WARN type messages:
* prod_add_fail, no_product, prod_delete_fail