[daip] AIPS and upgrades

[Eric Greisen]

Jose' Manuel Afonso writes:
 > 
 > Dear Eric,
 > a short question which I hope you can answer.
 > 
 > I have recently upgraded AIPS and all seems well, but it would be useful
 > to keep the definitions (parameters) of the tasks used previously. Right 
 > now when I use (for example)
 > > tget bpass
 > it replies:
 > AIPS 1: ZOPEN: FILE DA01:TGD0B4000.002;      NOT FOUND
 > AIPS 1: YOU SEEM TO HAVE NO FILES OF TYPE TG VERSION  0 OPEN ERR      2
 > which I assume is due to the non-existence of definition files from previous 
 > runs (the new installation is brand new... I have all the AIPS05 files safely 
 > away, though). Could I copy some file (which?) with all parameters of the tasks 
 > I was using before to the new installation? I guess it might conflict if a task 
 > in the new version has different parameters than previously, but you should now 
 > how to handle this, right? (I don't imagine any AIPS guru going through all the 
 > parameters everytime it upgrades...)
 > 

Normally one installs 31DEC06 parallel to 31DEC05 using all the same
data areas, control files, etc.  Thus, there is a $AIPS_ROOT/31DEC05
and a $AIPS_ROOT/31DEC06 directory trees and the data areas are
completely shared.  Then one can choose version 'tst' or version 'new'
for any task.  On occasion parameters change (in the middle of
developing the 31DEC06 version for example which we will continue to
do until the end of the year).  On these occasions a TGET may complain
about bad parameters or show messed up adverbs but they are easily
corrected by setting desirable values instead.  Note, if you have
installed 31DEC06, you will want to run the MNJ occasionally - once
every few weeks is usually plenty - to keep up to date.

If we should ever change things so that 2 versions are not compatible,
we will discuss that in detail in the AIPSLetter.  The ttape daemons
of really old versions (31DEC03 and earlier) are not compatible with
current ones, but that is all.

Eric Greisen