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

[Simon Clubley]

On 2019-01-22, Marc Van Dyck <marc.gr.vandyck at invalid.skynet.be> 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.
>
> 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 :
>
> 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.
>

As other people have effectively mentioned, I hope you aren't thinking
you need to use sys$qio() calls to do TCP/IP networking on VMS in C.

If that isn't the case, then what's the problem you are seeing ?

For example, does the code use fork() in the way it was intended to be used ?

Does the code require a fully functional select() call ?

> 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.
>

If you understand C enough to be able to port it to Pascal, then you
understand C enough to be able to tweak the existing code (if that is
all that is needed).

> 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...
>

Then you would have the same problems writing similar code on Linux.

Try reading some of the getting started guides for TCP/IP programming
on Linux, try the examples on Linux, and then try the same code on VMS.

Simon.

-- 
Simon Clubley, clubley at remove_me.eisner.decus.org-Earth.UFP
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