Customised error boxes in RO 3.1

I had always assumed that the ability to add user-defined
extra buttons to "error" boxes and replace the OK and
Cancel buttons with one's own legends was a feature only
from RISC OS 3.5 onwards. While testing a program on an
A5000 recently I was agreeably surprised to find my
cutomised "error" windows being displayed just like on my
RiscPC.

Exactly what enables this feature? Is it a module and, if
so, which one?

Derek Haslam

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Derek Haslam dhaslam atte boulsworth dotcodotuk
Powerbase Support http://www.boulsworth.co.uk/
.