TCP/IP options

From	Paul Edwards <mutazilah@gmail.com>
Newsgroups	comp.os.os2.programmer.misc
Subject	TCP/IP options
Date	2024-03-26 15:02 +0800
Organization	A noiseless patient Spider
Message-ID	<uttrtd$1lrs8$1@dont-email.me> (permalink)

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I have spent most of the last 3-4 decades writing
C90 applications, and since TCP/IP is not part of
C90, I haven't had anything much to do with it.

Using qemu I can connect a COM port to an IP address,
so I was able to write a crude nntp program that
did read/write to com1:. Even this was abstracted.
COM1: was just a filename to my app, and I opened
it as "r+b" and did an fseek of 0 from current
position to switch between read and write (a C90
requirement).

That code is here:

https://sourceforge.net/p/pdos/gitcode/ci/master/tree/src/pdpnntp.c

But a more generic app, allowing the user to provide
an address and connecting to that, cannot use the
above trick. And especially a web browser can't do
that, as I believe you need to disconnect and
reconnect whenever you want to get a new page as it
is stateless.

Although I suspect that I can probably use qemu and
com1 if I just want to retrieve the text at
http://pdos.org - I will try that.

So I do have one application that takes me outside
the capabilities of C90 fread/fwrite/fseek:

https://sourceforge.net/p/mvs380/mvssrc/ci/master/tree/ozpd/c/modem.c

And for whatever historical reason, I ended up using
the Unix API, and then Cygwin to allow that to run
on Windows. So that covers Linux and Windows - assuming
I want to stay with that interface.

I don't know what the native capabilities of OS/2 or
ArcaOS are, and nor do I know whether there is
something like Cygwin available for OS/2.

I could in fact write my own Cygwin for OS/2 that is
limited to just the TCP/IP functionality.

One thing that I don't like about the Unix interface
is that it uses "close" to close a socket, requiring
the OS to distinguish between sockets and files.

However, that's probably not a problem for me, as I
only access files via fopen in my apps, so close can
be dedicated to sockets.

Any idea where I stand?

So this is for the limited goal of a mini browser that
can read HTML pages in plain text and print the text
to the screen. And the browser will be public domain
C90 code other than the TCP/IP library extensions
(whatever is used). But my limited goal should still
cover Windows, OS/2 and Linux (but I am happy to
write code to interface with the underlying native
libraries). And I would normally target Windows 95
and OS/2 2.0 as the lowest common denominator, but
I can move forward if there is a compelling reason
to do so.

At this stage I am not trying to compete with Firefox
or anyone else. Just a very limited goal.

Thanks. Paul.

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Thread

TCP/IP options Paul Edwards <mutazilah@gmail.com> - 2024-03-26 15:02 +0800
  Re: TCP/IP options Paul Edwards <mutazilah@gmail.com> - 2024-03-26 16:32 +0800
    Re: TCP/IP options Paul Edwards <mutazilah@gmail.com> - 2024-03-26 19:34 +0800
      Re: TCP/IP options Paul Edwards <mutazilah@gmail.com> - 2024-03-26 19:53 +0800
      Re: TCP/IP options Paul Edwards <mutazilah@gmail.com> - 2024-03-27 07:36 +0800

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