header file question

[Geiregat Jonas]

I've got this small app , from 2 .c files. One file contains the main
and the other file contains functions used in the main. I compile this
using gcc like this: gcc -c *c && gcc -o app *o. But I want to do it in
an other way. I want to use header files I've googled but did not find
anything usefull expect that there should be prototypes in my header
file can anyone help me ?

[Sheldon Simms]

On Sat, 15 Nov 2003 11:52:28 +0000, Geiregat Jonas wrote:

I've got this small app , from 2 .c files. One file contains the main
and the other file contains functions used in the main. I compile this
using gcc like this: gcc -c *c && gcc -o app *o. But I want to do it in
an other way. I want to use header files I've googled but did not find
anything usefull expect that there should be prototypes in my header
file can anyone help me ?

It's not clear what you are talking about.
Try this:

gcc -o app *.c

[Aaron Walker]

Geiregat Jonas wrote:

I've got this small app , from 2 .c files. One file contains the main
and the other file contains functions used in the main. I compile this
using gcc like this: gcc -c *c && gcc -o app *o. But I want to do it in
an other way. I want to use header files I've googled but did not find
anything usefull expect that there should be prototypes in my header
file can anyone help me ?

I will do a small example.
main.c
------

#include <stdio.h>
#include "calc.h"

int main()
{
int x;
printf("Enter an integer: ");
scanf("%d", &x);
printf("The square of %d is %ld\n", x, square(x));
return (0);
}

calc.h
------
#ifndef CALC_H
#define CALC_H

long square(int);

#endif

calc.c
------
#include "calc.h"

long square(int x)
{
return ((long) x * x);
}

---------
NOTES
notice the quotes when including calc.h because it is in the same
directory as the source file

also, if you've never used preprocessor directives, the "#ifndef
CALC_H" may look confusing. You want this in the header file, though.
It prevents multiple inclusions of that header file. Just change CALC_H
to whatever.. I dont think it matters as long as its the same as the
#define statement below it.

HTH,
Aaron

[tuchka]

Look at an article at this link.
It is good simple tutorial on C programming and also there detailed
instructions how to make library at 'libraries' link using gcc
compiler. (I've done that and it worked).

http://computer.howstuffworks.com/c.htm
tuchka

[Richard Heathfield]

tuchka wrote:

Look at an article at this link.
It is good simple tutorial on C programming and also there detailed
instructions how to make library at 'libraries' link using gcc
compiler. (I've done that and it worked).

http://computer.howstuffworks.com/c.htm

The first incorrect statement I spotted was at

http://computer.howstuffworks.com/c1.htm

Here it is:

"C is what is called a compiled language. This means that once you write
your C program, you must run it through a C compiler to turn your program
into an executable that the computer can run (execute)."

The second, related error:

"...to write and run a C program, you must have access to a C compiler."

The third error:

"When you enter this program, position #include so that the pound sign is in
column 1 (the far left side). Otherwise, the spacing and indentation can be
any way you like it."

Counter-example:

#include<stdio. h>intmain(){p r i n t f("This is output from my first
program!\ n"); return0;}

When Mr Brain has fixed those errors, I'll find some more for him to do.

--
Richard Heathfield : bi****@eton.pow ernet.co.uk
"Usenet is a strange place." - Dennis M Ritchie, 29 July 1999.
C FAQ: http://www.eskimo.com/~scs/C-faq/top.html
K&R answers, C books, etc: http://users.powernet.co.uk/eton

[Joona I Palaste]

Richard Heathfield <do******@addre ss.co.uk.invali d> scribbled the following:

tuchka wrote:

Look at an article at this link.
It is good simple tutorial on C programming and also there detailed
instructions how to make library at 'libraries' link using gcc
compiler. (I've done that and it worked).

http://computer.howstuffworks.com/c.htm

The first incorrect statement I spotted was at http://computer.howstuffworks.com/c1.htm Here it is: "C is what is called a compiled language. This means that once you write
your C program, you must run it through a C compiler to turn your program
into an executable that the computer can run (execute)."
I don't see how that statement is incorrect.
The second, related error: "...to write and run a C program, you must have access to a C compiler."
Hmm, I can see two ways to parse that as erroneous.
1) If writing a program merely consists of writing the source code,
you don't need a compiler.
2) You don't need *any* programming tools to run programs.
But does "to write and run a C program" mean "to write a C program
and then to run the same C program" or "to write a C program, and
to run (possibly another) C program"?

(snip third error)
When Mr Brain has fixed those errors, I'll find some more for him to do.

--
/-- Joona Palaste (pa*****@cc.hel sinki.fi) ------------- Finland --------\
\-- http://www.helsinki.fi/~palaste --------------------- rules! --------/
"You can pick your friends, you can pick your nose, but you can't pick your
relatives."
- MAD Magazine

[Richard Heathfield]

Joona I Palaste wrote:

Richard Heathfield <do******@addre ss.co.uk.invali d> scribbled the
following:

The first incorrect statement I spotted was at

http://computer.howstuffworks.com/c1.htm

Here it is:

"C is what is called a compiled language. This means that once you write
your C program, you must run it through a C compiler to turn your program
into an executable that the computer can run (execute)."

I don't see how that statement is incorrect.

http://eic.sourceforge.net/ is one of several counter-examples.

--
Richard Heathfield : bi****@eton.pow ernet.co.uk
"Usenet is a strange place." - Dennis M Ritchie, 29 July 1999.
C FAQ: http://www.eskimo.com/~scs/C-faq/top.html
K&R answers, C books, etc: http://users.powernet.co.uk/eton

[Aaron Walker]

Richard Heathfield wrote:

http://eic.sourceforge.net/ is one of several counter-examples.

This is most excellent ;) I didn't know they had C interpreters now.. heh.

[Dan Pop]

In <t%************ **********@twis ter.tampabay.rr .com> Aaron Walker <ka*****@REMOVE THIScfl.rr.com> writes:

Richard Heathfield wrote:

http://eic.sourceforge.net/ is one of several counter-examples.

This is most excellent ;) I didn't know they had C interpreters now.. heh.

They've been around for quite a while.

Dan
--
Dan Pop
DESY Zeuthen, RZ group
Email: Da*****@ifh.de

[Richard Heathfield]

Aaron Walker wrote:

Richard Heathfield wrote:

http://eic.sourceforge.net/ is one of several counter-examples.

This is most excellent ;) I didn't know they had C interpreters now.. heh.

The first time I used a C interpreter was in 1989. (HiSoft C for the Atari
ST.)

--
Richard Heathfield : bi****@eton.pow ernet.co.uk
"Usenet is a strange place." - Dennis M Ritchie, 29 July 1999.
C FAQ: http://www.eskimo.com/~scs/C-faq/top.html
K&R answers, C books, etc: http://users.powernet.co.uk/eton