Re: back-tab locks up 0.17.3 in Windows, with fix

On Tue, 18 Nov 2008, Buck wrote:

Here's the scenario:
Start tn5250, sign on to System i.
wrkmbrpdm
Position cursor to row 7, column 11. This is the first character of the
member name column.

I think you have the column and row mixed up. The member name column begins on row 11, column 7.

Shift-tab.
Lock up.

This is not happening to me.

I believe there's a missing 'break;' in
tn5250_display_set_cursor_prev_progression_field

I believe that the code is correct and that there should not be a break there. I'm pulling up some very old and dusty memories here, but I believe it is coded that way because of the ordering of the fields as tn5250 receives them from the host. What this function is trying to do is find the previous field as defined by cursor progression which is different than the field ordering as given tn5250 by the host. If there is only one field on the screen than differentfieldfound will always be zero and clearly we need to break out of the loop. Otherwise we want to keep looping through the list of fields, which could be in any order. Once we find the field which is the previous cursor progression field we want to break. If we never find such a field, then we break when we loop all the way back to the field we started on. Either way, we should never get stuck in an infinite loop because the field list is a linked list that points to itself so eventually the second case will always be true.

You do have a rather old version of the source. The most recent version is 0.17.4 and that has been rock solid for me for a very long time now. If after updating you still have this problem please report back.

James Rich

if you want to understand why that is, there are many good books on
the design of operating systems. please pass them along to redmond
when you're done reading them :)
- Paul Davis on ardour-dev