Understanding the PROMPT instruction

The PROMPT instruction is used to query for a single value from the user.

PROMPT requires the text of the question to be displayed to the user and the variable that receives the value entered by the user. The variable can be of any simple data type except TEXT and BYTE.

The runtime system displays the question in the prompt area, waits for the user to enter a value, reads whatever value was entered until the user validates (for example with the Enter key), and stores this value in a response variable. The prompt dialog remains visible until the user enters a response.

The prompt finishes after ON IDLE, ON ACTION, or ON KEY block execution (to ensure backward compatibility).

Prompt display in TUI mode

In TUI mode, the PROMPT question and input field is displayed in the prompt line of the current window, which is defined by the OPTIONS PROMPT LINE instruction or with the ATTRIBUTES clause of OPEN WINDOW.

Note: If the prompt line is not as wide as the prompt string and the size required for the variable input, runtime error -1146 occurs.

Prompt display in GUI mode

In GUI mode, the PROMPT instruction opens a modal window with an OK and a Cancel button, and waits for input from the user.

Figure: PROMPT window (Linux/Gnome GDC)