Making CA calls from multi-threaded programs???

[Leonard Reder <reder@huey.jpl.nasa.gov>]

Hello,

I am developing sequencing code using a case tool called
Rhapsody.  This is part of the Keck Interferometer control
system and talks to EPICS PVs via a Keck Keyword API layer on
top of Channel Access.  I assume the Keyword API is built
on the portable CA libraries.  Currently running EPICS
3.13.0 Beta 12 at Keck and I assume the Keyword library
is linked to this.  Well up until now my Keywords (PVs) where used
in two threads and seemed to work just fine.  But I had
to add a keyword to a third thread and the following error
message is given:

CAC: unexpected select fail: 9=Bad file number
Segmentation fault

And my program segment faulted as shown.  Found this
message in $EPICS/base/src/ca/bsd_depen.c.  It is not
that the code does not run but rather this happens after
the code is running for a few minutes.  Any ideas about
exactly what is going on here?  Could an upgrade of EPICS
help this situation?

Thanks,

Len