IBM Mainframe Forum

Hi,
In an interview I was asked "tell the logic behind F7 (up) and F8(down) keys?"
I answered "I am afraid that I am unaware of that sir"

Any suggestion on this are welcome.
Thanks

the question as posed is bit foggy.

why the choice of PF7/PF8 for scrolling ?

what code is invoked when one of those key is pressed ?

WHAT APPLICATION is the interviewer referring to ?

as You see, if You want good answers You need to ask good questions

Well I presented the question in the way it was asked to me,no additions from my side.
Thanks

You're missing what enrico is saying.

Without knowing specific application details, there is no way to answer the question, other than "they could do whatever you like". PF means "Program Function" . The function for any PF-key is whatever that, particular, specific program provides.

Without knowing anything, you could "guess" that PF7/8 are to present the previous/next logical screen, but you should tell this to the interviewer with the rest of the explanation.

What does PFn do? Whatever I (or a program) tells it.

I think the interviewer must be trying to ask the scroll logic using the PF7/PF8 keys.
While browsing the file the system will throw the number of records which it can accommodate on screen. and store the key of the first and last record which is displayed.
Then on pressing PF8 it will display the next set of records starting from the next record which was last displayed.
In case of PF7 it will display the previous set of records than the first one which was displayed.

the system will throw the number of records

The system does not THROW anything. It displays it. THROW is NOT mainframe terminology.

NicC wrote:

the system will throw the number of records

The system does not THROW anything. It displays it. THROW is NOT mainframe terminology.

Great

There are other methods also. Like using a TSQ.