Chapter 11. Debugging And Error Recovery Techniques; Suspended Function Execution - IBM 5110 User Manual

Chapter 11. Debugging and Error Recovery Techniques
SUSPENDED FUNCTION EXECUTION
The execution of a user-defined function can be interrupted
(suspended) in a variety of ways: by an error message, by pressing
the ATTN key, or by using the stop control vector (S6). In any case,
the suspended function is still considered active, since its execution
can be resumed. Whatever the reason for the suspension, when it
occurs, the statement number of the next statement to be executed is
displayed. A branch to the statement number that was displayed or a
branch to DLC(+DLC) causes normal continuation of the function, and
a branch out (+0) removes the function.
When a function is suspended, the 5110 will:
• Continue to execute system commands except )SAVE, }COPV, and
)PCOPV.
• Resume execution of the function at statement n when +n is
entered.
• Reopen the definition of any function that is not pendent. A
pendent function is a function that called the suspended function. If
a function called a function that called a suspended function, it is
also pendent (see State Indicator).
• Execute other functions or expressions.
• Execute the suspended function again.
Note: The display of output generated by a previous statement might
have been interrupted when the suspension occurred. This would be
caused by the delay between execution of the statement and display
of the output.
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