Managing Serial Ports

Hi all:

I want to know how to manage messaging process when i use readcond() and
ionotify() functions.
We have all runing in QNX 4.25 and using dev_read. Migrating documents says
that dev_read must be changed with devcond and ionotify, but when you use
ionotify(), how we must manage this??

All your help we 'll be appreciated.
TIA
David