[talk] possible meeting topic: FreeBSD desktop stuff with a side of DJ-BSD redux

[James K. Lowden]

On Tue, 04 Mar 2025 21:38:03 +0100
Tara Stella <tara at tara.sh> wrote:

Hi Tara, and welcome!  

> Believe it or not, I'm learning COBOL now. I am not a developer, I
> consider myself more of a sysadmin, 

I think many denizens of NYCBUG would describe themselves the same way. 

> but I love the idea of having a language that spans from old MVS 3.8j
> to more modern systems including FreeBSD and Linux, that is stable
> and don't require fancy dependencies and, last but not least,
> produces small binaries. 

That depends, if you will, on what "fancy" and "require" mean.  And,
for that matter, "small".  

Like most compiled languages, COBOL requires a runtime library to
mediate between the logic of the program and the outside world.
Something in the executing environment defines what READ and WRITE mean
on the computer.  COBOL is more demanding of that environment than,
say, C.  There is no notion of an unhosted environment, and COBOL I/O
defines random-access and key-indexed record-based file operations.  

To support that in a Posix environment, where all files are a stream of
bytes and record-oriented I/O is anathema, GnuCOBOL and gcc-cobol
supply record-oriented I/O operations in their runtime libraries.  On
the mainframe that's not necessary because the OS provides those
services.  There, rather than constructing those services for
itself from scratch, COBOL just hooks into them.  

That is the crux of the migration challenge, by the way.  Just as
apache and postfix expect a webserver and chmod(2), COBOL applications
have requirements of their environments.  There is no VSAM emulation in
the FreeBSD port system.  There is 3270 terminal emulation, but nothing
like a CICS transaction monitor.  There is nothing like IMS.  Being
able to recompile the application is necessary precondition, but only
one.  

> I would love to learn more about it. At the moment I'm using GnuCOBOL
> on both Linux and FreeBSD. I'm far from an expert, and this is mostly
> out of curiosity, are you targeting a specific COBOL standard?

Our gcc-cobol references the ISO 2023 COBOL standard.  To my knowledge,
no compiler fully implements it.  I would explain why but 1) it's
off-topic and 2) it wouldn't be much use to you unless you wanted to
pony up to buy a copy.  There is also a "-dialect ibm" option to accept
IBM syntax.  IBM's documention is online and their compiler is largely
consistent with ISO.  Any failure of gcc-cobol to compile IBM syntax
using the -dialect option is considered a bug.  

If you decide you'd like to try gcc-cobol, you'll need to build it from
source.  It's easy, we do it every day.  I've never built it on
FreeBSD, but if you go down that road and have difficulty, I'd be glad
to help.  

--jkl