[daip] data disks

[Eric Greisen]

There are several ways to do this, but you need first to understand
one rule.

On machine XXX, aips start-up looks for data areas named XXX, e.g.
/home/AIPS/DATA/XXX_1.  There is no requirement that the actual disk
be on XXX, just that its name is XXX and that machine XXX can mount
it.

One can also declare a data area to be "required" for all computers at
the site - put a + sign in the first column rather than a minus sign.
Then if there is a data are with a + and no XXX areas, the only area
will be the one with the plus.

A third choice would be to remember to say da=yyy on the command line
to include the disks named YYY.

Eric Greisen