Monday, January 16, 2017

Priority trick for screen procedures

Whilst checking something buried in a screen procedure within Priority, I came across the following nugget:
SELECT 420, 539 INTO :WRNMSG, :GOTO FROM DUMMY WHERE :RETVAL <= 0;
I wrote a quick procedure which confirmed what I thought this snippet does: if the variable RETVAL is less or equal to zero, then warning message 420 will be displayed and execution will skip to label 539. As it happens, earlier this morning I had written something much less concise than this to achieve the same result, so the find was quite serendipitous.

Here are two more undocumented variables which can be added to one's private toolbox.


Sunday, January 08, 2017

A cold day in London

It's comparatively very cold here, although I know that the temperature is at least 5-10 degrees C higher than Europe. We feel the cold more, though, as the area where I live is open to winds which blow the cold air from the Russian steppes. The wind isn't as strong in cities.

Driving home on the motorbike today, I was reminded of a day 39 years ago (I don't remember the exact date, only that it was in the first week of the spring term of 1978), so it may as well have been exactly 39 years ago. I came out of the university - I think after lunch, as there was plenty of light - and started driving home. I don't remember which route I used to take from the Elephant and Castle/Borough area to Hampstead, although I do remember that I would drive through Camden, Chalk Farm, up Haverstock Hill, onto Hampstead High Street, then skirt around the Heath until I got to the back street which led to where I lived on Finchley Road.

When I left the university, it was cold but dry; some time after Waterloo Bridge, it began to rain. As I drove further north, the rain turned to sleet, and by the time I was nearly home, snow was falling. It's very difficult driving on in a motorbike through snow, and I remember that the final back street was almost virgin - no one had cleared a path. My coat had a layer of ice on it!

Unsurprisingly, I decided to travel to the university the next morning by underground.