programming languages and visual programming under FreeBSD

[Giorgos Keramidas]

On 2005-01-16 20:23, koen de wijs <koendewijs at gmx.net> wrote:
> I heard that C is the most powerfull language under unix and almost
> the complete system is written under it.  You can do everything with
> it. Where is a good toturial?

Many good C resources are available online at:

    http://www.eskimo.com/%7Escs/C-faq/top.html

You can also find some references for printed books there.  The C
language is not difficult to start using, but there _are_ some finer
points that newcomers can grasp more easily after reading a few
printed books.

> Can you read and write directly with the printer port or does the
> kernell block that?

Accessing the hardware directly is one of the most unportable things
you can do with C and UNIX.  You should try using the proper device
file instead, if possible.

For printers that would be /dev/lpt0, /dev/lpt1, etc.

> I got a programm from someone that putted some assmebler in his c
> programm to adress the printer port.

Very unportable, as I said above.  Writing a C program that uses
fopen() or open() on the /dev/lpt0 file (or any other lpt device),
would be much preferable.

> And where can I find an overview of all the *.h files that you can
> use under FreeBSD

The manpages that define the relevant APIs are usually your best bet.
Then, when you are experienced enough with C you may start reading the
*.h files under /usr/include directly.

> Are there any visual programming tools under FreeBSD, like click and
> drag like microsoft visual c?  The only options that I found where:
> GTK, KDE libs and Gnome libs or directly tlak with the x server.

I'm sure there are some.  A lot of people like using IDEs like
KDevelop or Eclipse.  The good thing about the compilers and other
tools of FreeBSD is that you don't *have* to use an IDE though.

A good editor is usually all one needs.  This is why many people
prefer to stay away from IDEs altogether and use vim or Emacs to edit
their programs instead.

> The other languages that I know are: Perl, I could only find that it
> is especially for tasks for your system and that it's based on C Shell
> scripts, for tasks for your systems and simple programms Python.
>
> What are the advantages of these languages above C and are there more
> programming languages under FreeBSD?

This is a very difficult question to answer without getting you to learn
all the relevant languages first.  Every language has its own merits, I
guess.  You can learn as many of them as you like, or you can pick 2-3
of them and stick with them.  The choise is yours to make...

- Giorgos