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Include header file problem !! on ANSI - C

Dear all,

I have written my own function by C. And my development platform is
W2k with VC6.0.
Then I also defined a header file to extern declare this function.
After that, I include this header file.

The function is stored in C:\temp\myfun.c
int func(){
return 1;
}

The header file is stored in C:\temp\myheader.h
extern int func(void);
in my main program, I got a problem if I include this header file
(myheader.h).
#include <stdio.h>
#include "C:\temp\myheader.h"

void main(){
func();
}

This main program is not in c:\temp\ folder.
The error message is {
--------------------Configuration: pureC_test - Win32
Debug--------------------
Compiling...
main.c
Linking...
main.obj : error LNK2001: unresolved external symbol _func
Debug/pureC_test.exe : fatal error LNK1120: 1 unresolved externals
Error executing link.exe.
Creating browse info file...

pureC_test.exe - 2 error(s), 0 warning(s)

}

BUT if I copy the myfun.c & myheader.h in the same path as the main
program. It works fine.

Can anybody help me to solve this problem??

Thank you very much.
Alan
Nov 13 '05 #1
6 6892
alan wrote:
.... snip ...
The function is stored in C:\temp\myfun.c
int func(){
return 1;
}

The header file is stored in C:\temp\myheader.h
extern int func(void);

in my main program, I got a problem if I include this header file
(myheader.h).
#include <stdio.h>
#include "C:\temp\myheader.h"
Those backslashes are escape characters. \t means a tab char. \m
is not defined, but most likely is taken as m. Either use forward
slashes, or double the backslashes.

.... snip ...
Can anybody help me to solve this problem??


--
Chuck F (cb********@yahoo.com) (cb********@worldnet.att.net)
Available for consulting/temporary embedded and systems.
<http://cbfalconer.home.att.net> USE worldnet address!

Nov 13 '05 #2
In article <7b**************************@posting.google.com >,
ch***********@i-cable.com says...
in my main program, I got a problem if I include this header file
(myheader.h).
#include <stdio.h>
#include "C:\temp\myheader.h"
This is all off-topic for CLC, which only talks about the standard
C language, not compiler-specific build environments and their
problems. One of the microsoft newsgroups is probably your best
bet.

However... Using VC, without an external make file, the usual way of
doing this is to add the directory to your include path in the
project itself, then simply use
#include "myhdeader.h"

void main(){
func();
}

This main program is not in c:\temp\ folder.
The error message is {
--------------------Configuration: pureC_test - Win32
Debug--------------------
Compiling...
main.c
Linking...


Notice, it never compiled myfun.c. That's because the source file also
must be added to the project. The unresolved external is due to there
not being an object file containing func(). Add the source file, do
a build all, and you should be good to go.

Nov 13 '05 #3
CBFalconer <cb********@yahoo.com> wrote in message news:<3F***************@yahoo.com>...
alan wrote:
... snip ...

The function is stored in C:\temp\myfun.c
int func(){
return 1;
}

The header file is stored in C:\temp\myheader.h
extern int func(void);

in my main program, I got a problem if I include this header file
(myheader.h).
#include <stdio.h>
#include "C:\temp\myheader.h"


Those backslashes are escape characters. \t means a tab char. \m
is not defined, but most likely is taken as m. Either use forward
slashes, or double the backslashes.

It's true.In addition,the content of 'myheader.h' should be
int func(void);
The word of extern isn't needed.
... snip ...

Can anybody help me to solve this problem??

Nov 13 '05 #4
CBFalconer wrote:

alan wrote:

... snip ...

The function is stored in C:\temp\myfun.c
int func(){
return 1;
}

The header file is stored in C:\temp\myheader.h
extern int func(void);

in my main program, I got a problem if I include this header file
(myheader.h).
#include <stdio.h>
#include "C:\temp\myheader.h"


Those backslashes are escape characters. \t means a tab char. \m
is not defined, but most likely is taken as m. Either use forward
slashes, or double the backslashes.


Nit-pick: The backslashes are *not* escape sequences,
and \t does *not* mean a tab character. The stuff between
the double quotes is a "q-char-sequence," *not* a string
literal.

6.4.7 Header names
/3/ [...] Similarly, if the characters ', \, //, or /*
occur in the sequnce between the " delimiters, the
behavior is undefined(68)

68) Thus, sequences of characters that resemble escape
sequences cause undefined behavior.

The practical consequence is that the form of header names
is platform-dependent, and it's up to the platform to decide
what (if anything) to do with backslashes and the like. The
O.P.'s compiler may or may not accept them -- and doubling
the backslashes may or may not cure the problem.

--
Er*********@sun.com
Nov 13 '05 #5
sorry, I made a type mistake on path slash char.
I repeat my question.

I defined a header file to extern declare this function.
After that, I include this header file.

The function is stored in C:\\temp\\myfun.c
int func(){
return 1;
}

The header file is stored in C:\\temp\\myheader.h
extern int func(void);
in my main program, I got a problem if I include this header file
(myheader.h).
#include <stdio.h>
#include "C:\\temp\\myheader.h"

void main(){
func();
}

The main program , say "main.c" is stored in another location.
But if I copy the myfunc.c & myheader.h to the same path of "main.c",
it works fine.

My question is why my main.c program cannot locate "myfunc.c" & "myheader.h" file ??

Can anybody help me?

Pls help!!

Thank you very much.

Randy Howard <ra**********@FOOmegapathdslBAR.net> wrote in message news:<MP************************@news.megapathdsl. net>...
In article <7b**************************@posting.google.com >,
ch***********@i-cable.com says...
in my main program, I got a problem if I include this header file
(myheader.h).
#include <stdio.h>
#include "C:\temp\myheader.h"


This is all off-topic for CLC, which only talks about the standard
C language, not compiler-specific build environments and their
problems. One of the microsoft newsgroups is probably your best
bet.

However... Using VC, without an external make file, the usual way of
doing this is to add the directory to your include path in the
project itself, then simply use
#include "myhdeader.h"

void main(){
func();
}

This main program is not in c:\temp\ folder.
The error message is {
--------------------Configuration: pureC_test - Win32
Debug--------------------
Compiling...
main.c
Linking...


Notice, it never compiled myfun.c. That's because the source file also
must be added to the project. The unresolved external is due to there
not being an object file containing func(). Add the source file, do
a build all, and you should be good to go.

Nov 13 '05 #6
In article <7b**************************@posting.google.com >,
ch***********@i-cable.com says...
My question is why my main.c program cannot locate "myfunc.c" & "myheader.h" file ??

Can anybody help me?

Pls help!!

I already answered your question, included in the quoted text of your
reply. I give up.

Nov 13 '05 #7

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