[Info-vax] Help wanted : Porting code from Linux to VMS

[Dave Froble]

On 1/22/2019 3:44 PM, Marc Van Dyck wrote:
> My job today is mainly system administration. But I have done software
> development in the past, and still enjoy doing some programming when the
> opportunity arises. What I have been asked to do today is however a bit
> more challenging for me than usual.

Welcome to the dark side ...

> It'll basically consist of porting C code written for a linux platform
> to OpenVMS. And it won't be the trivial 'copy the code and recompile'
> job :

Why not?  Have you tried it?  That should be one of your earlier steps. 
  Who knows, it, or most of it, just might work.  Not giving this a 
chance just isn't too smart.

> 1) it contains several system calls which I'll need to find an adequate
> equivalent for. I think I can manage that one, even if I know nothing
> about Linux.

Do you have specifics?  Others have mentioned that the VMS C-RTL might 
have all that you need.

> 2) I will port the code from C to Pascal, which is the only language I
> feel comfortable with. Not afraid by that one, have done it several
> times already.

That is not a port.  That is a re-write, and even perhaps a re-design. 
Would not be my first, or second, or even third choice.

> 3) The code contains a good dose of TCP/IP programming. And there I'm
> somewhat lost, because I never touched that in the past. So I'd
> appreciate a bit of help to get me started...

Some examples can help.

> Hence the following questions :
>
> 1) Is there any documentation about that ? How to write, on OpenVMS,
> code to establish a TCP/IP communication with another host ? Like what
> you would do with DECnet non transparent task to task communication ?

Others have mentioned the correct TCP/IP manual.  I was able to muddle 
through most of it.

> 2) Any coding examples availabe somewhere, or that someone would agree
> to share ? Preferably in Pascal, but I'll understand if only C is
> available...

I'll attempt to send you some of the stuff from when I was figuring this 
out.  They will be much better for learning that our actual production 
stuff.

Note, if you need SSL/TLS and such, that is a different beast.  I had 
Steve write some stuff for me, since I detest C, can read it a bit, 
cannot write it, and DON'T WANT TO!

Rather pertinent question, if using SSL, from whom, and what version. 
They are not very compatible.

> 3) Are the TCP/IP calls definitions that I'll need to use available
> in pascal environment files somewhere ? Or SDL definitions that I
> could translate and compile ?
>
> If you want to send me something, the address is
> marc dot gr dot vandyck at skynet dot be.
>
> Many thanks in advance for all your hints !
>
>


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David Froble                       Tel: 724-529-0450
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