Programming in C on RISCOS

I keep on running into similar issues.
Where I know the function call I need to use.
In my current case I’m switching from using fopen/fputs to using open/write.
I know how open/write work perfectly well.
However finding the header to include ends up me using !Find to trawl through the header files, which is irritating – but doable.
However getting link errors is a nightmare…

ARM Linker: (Error) Undefined symbol(s).
ARM Linker: open, referred to from @.o.sockets.
ARM Linker: Errors in link, no output generated.
ARM Linker: finished, 2 informational, 0 warning and 1 error messages.
AMU: * exit (1) *

I’ve looked in the pdf’s and these aren’t so useful to be honest, they are huge and don’t contain any information that I don’t already know.
Now I’m hoping I’m being dumb and missing something. But the include was in TCPIPLibs (for some random reason that I can’t fathom, as socket reads and writes seem to be handled by socketwrite/socketread function)
I’m using the socket code fine and am referencing all of the .o files in TCPIPLibs so why would I get a link error?

What method should I use to find the link library, or is banging my head against the wall the best method (the wall does fall, it just takes a long time and it hurts my head) ;-)

One very useful thing would be to get all the C related StrongHelp manuals. Not because they explain everything – they don’t – but because if you type a likely api name and hit F1 (in StrongEd, which of course you are using, why wouldn’t you?) then it will not just remind you of the api & arguments but tell you which include file it is from.

open() is a POSIX function which the DDE doesn’t support. Hence the undefined symbol.
Another option is to use GCC with UnixLib which does include support for open amongst others.

In general there is a problem with documentation for C programming in RISC OS—not a good way of attracting potential developers. The main issues I see are:

• The API is documented heavily at ARM assembly level but the brief references to C in the PRMs don’t even state what the relevant header files are.

• Most of the existing tutorial documentation on GUI programming is based on BASIC. Yes, there was a C-based series in Archive magazine, and republished as a booklet, but it is incomplete.

• StrongHelp-based documentation is generally very terse.

It also doesn’t help that none of the existing cross-platform GUI toolkits—Qt/Gtk/wxWidgets/FOX/FLTK etc etc, works on RISC OS. This makes the need to create tutorial information based on C particularly important.

Thanks very much!
@Chris well looks like I was banging my head against an “invisible” wall then! It’s been a while, I had completely forgotten there was anything other than POSIX. My ignorance.
Bizarre how it’s referenced in the header files though!
@David I’ll muddle my way through and try and remember this isn’t UNIX! But I really don’t want to use Qt/Gtk, been there before – I fancied something that would test me, this certainly is!
I was thinking about writing a blog about programming in C on riscos, if I get the time and can summon the effort It’s a great idea – if nothing else would be a good reference for me!