BREAK Statement

Enables or disables the break function on the terminal.

Syntax

BREAK {KEY} OFF

BREAK {KEY} ON

BREAK expression

Syntax Elements

expression is any valid DataBasic expression that evaluates to a numeric value.

If expression evaluates to zero, the break function is disabled.

If expression evaluates to a nonzero value, the break function is enabled.

Operation

BREAK OFF disables the break function on the terminal. This can be used to prevent a user from stopping program execution during a critical process, such as a file update.

BREAK ON restores normal operation to the break function where pressing BREAK or CTRL+BREAK causes a "break" to the DataBasic symbolic debugger. Normal operation is also restored when the program ends.

Comments

The current state of the break function can be determined using the SYSTEM(23) function.

Note

These statements should only be used in a debugged program. If a program gets into an endless loop while the break function is disabled, you cannot stop the process on the terminal on which it was started.

Examples

BREAK KEY OFF
WRITE ITEM ON FILE,A

Disables the break function on the terminal while ITEM is being written to a file. This prevents interruption of the attempt to update the FILE, even if the BREAK (or CTRL+BREAK) key is pressed.

BREAK ON

Re-enables the break function.

BREAK X+5

Enables the break function if X+5 is nonzero, otherwise, the break function is disabled.

:ENABLE-BREAK-KEY

This TCL command re-enables the break function on the current terminal.