I have an unusual motive for asking this question but the answers might be useful in other contexts also. 

1) Is the BSD Operating System for the Polisy 32 bit or 64 bit? (Not the hardware) 

2) Does the processor have a Floating Point Unit? 

My reason for asking is I am wondering whether I can install Dyalog APL for Unix.   If not I can continue to use it on a Raspberry PI, which might be easier anyway.  This motivates a third question:

3) Does the Polisy have any additional facilities (compared to the ISY 994i where I currently use the REST interface) for moving data back and forth to another computer (in this case a Raspberry PI)  ?

Thanks very much

1) I'd imagine the OS is compiled for an AMD64 compatible CPU, so it would be 64 bit.

[admin@polisy ~]$ uname -a
FreeBSD polisy 13.0-RELEASE-p5 FreeBSD 13.0-RELEASE-p5 #14 releng/13.0-n244765-2646dd66590: Wed Dec  8 22:59:39 UTC 2021     
ec2-user@bsdev.isy.io:/usr/obj/usr/src/amd64.amd64/sys/POLISY  amd64

2) I've understood that an FPU is standard on any modern CPU (at least since the Intel Pentium CPUs).

3) You should have the use of NFS and Samba, along with the SSH suite of tools, such as scp and sftp.  All a bit of a learning curve if you're not familiar with the *nix command line, but the tools are there.

Edited January 3, 20223 yr by Bumbershoot

BSD is not the same as Linux.  Both can be called "unix" in a sloppy sort of way, but one cannot usually expect that a program compiled for one can run on the other.

One can have "source" compatability, meaning that when the code was written, care was taken to ensure that it would compile on both BSD and on LInux (and usually on other "unix-like" operating systems).  In this case, you would look for a binary version of your software that would run on FreeBSD 13 on a 64-bit Intel platform.

Binary compatability is possible, in limited cases.  In this situation, you would need to obtain a copy of the binary code for your software suitable for 64-bit Intel, in a "non-installer" format (e.g. a tarball or zip archive -- it's unlikely that any normal Linux installer (e.g. rpm/apt) would run on BSD).  You would need to install the linux-compatability packages (there may be a number of these) required to suppot your software -- there's no good way to know the full set of libraries, nor how to go from an error message to the correct BSD package to install.  The good news is that it's possible to do this; I've done it.  The bad news is that it's not something you want to do on the Polisy.

NFS works, although like any shared network filesystem, that poses risks to the stability of the Polisy due to "funny stuff" that can happen on your network -- I'd suggest treating the Polisy like you'd treat any server in a datacenter, and not add any dependencies that you don't absolutely need.  Stick with REST calls and SSH/SCP. 

Thanks @mwester and @bumbershoot. 

Dyalog directly supports RPM- and DEB-based Linux distros and AIX (IBM Unix) but apparently not FreeBSD.   So I'll stick to the raspberry PI (32 bit) and continue co-processing...    Thanks!