Writing portable software

[Jason Curl]

Dear C group,

I'm very interested in writing portable C, but I only have GNU, Sparc
and Cygwin to compile on.

What I find is the biggest problem to writing portable C is what headers
to include. What sites do people know about that are comprehensive in
their differences?

For example, MacOSX complained about <string.h>. With Solaris I needed
to include another header file other than <fcntrl.h> to get definitions
for changing the nonblocking status of reading/writing files.

If there is a definitive guide between "modern" systems, this would be
very helpful.

TIA.
Jason.

[Flash Gordon]

Jason Curl wrote:

Flash Gordon wrote:

Jason Curl wrote:

Dear C group,

I'm very interested in writing portable C, but I only have GNU, Sparc
and Cygwin to compile on.
<snip>

I've read K&R 2 a long time ago and staying to the C90 standard I agree
is the best.
Well, you should keep a copy handy as a reference. Mine is sat on my
desk at work.

<snip>
For example, MacOSX complained about <string.h>.

It should not complain about string.h since that is an ISO standard
header. Query that on a MacOSX group.

Sorry - I don't have MacOSX, a friend of mine has and he compiled
something for me. The solution to the problem was including another
header file, don't remember exactly what - strings.h or string.h.

Well, either you were using a non-standard function or your friends
install was broken.

With Solaris I needed
to include another header file other than <fcntrl.h> to get
definitions for changing the nonblocking status of reading/writing
files.

That is beyond what ISO C provides, so you will have to decide what
systems you want to be portable to and see if there is a common standard.

Any suggestions of other newsgroups I could ask? I guess specific
newsgroups would only give me information specific to a compiler or
platform, but what is really needed is some kind of comparison list.
I've seen that GNU AutoConf tools documentation contains a small list.

I would suggest that comp.programmin g would be a good start.

If there is a definitive guide between "modern" systems, this would
be very helpful.

There is probably no definitive guide for things outside ISO C that I
am aware of since Windows and *nix are rather different. However,
there are libraries ported to a number of systems that can help with
portability.

Narrowing down the search, if we remove "Windows" and go for POSIX-like
systems (e.g. QNX, BSD, GNU, Cygwin, MacOSX).

If you stick to POSIX like systems, comp.unix.progr ammer would be a good
place to start.

You *may* find that Windows groups can help with the differences between
Windows and POSIX, failing that comp.programmin g. It *is* possible to
write SW that goes beyond the C standard that runs on Windows and *nix,
but depending on what you want to do it can take a bit of work.
But most of all, thanks for the help so far.

OK, but now you have a better group to ask in for the bits beyond the C
standard.
--
Flash Gordon
Living in interesting times.
Although my email address says spam, it is real and I read it.