Message-ID: <37F16793.4D98B7CE@virtualis.com>
Date: Wed, 29 Sep 1999 11:12:51 +1000
From: Alex Mendes da Costa <alexmdc AT virtualis DOT com>
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Subject: Re: Newbie Question
References: <37F065E4 DOT 2C3B57D5 AT virtualis DOT com> <37F0EF05 DOT B46FB474 AT crosswinds DOT net>
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Okay, so now I have a header file with my routines declared and globals
and stuff called "subs.h" and I have a c program containing all these
subs called "subs.c" and I have a program called "prog.c" which contains
the line '#include "subs.h"'. I try to compile this using GCC (ie gcc
prog.c -o prog.exe) and I get error messages for all my subs which say:
c:/djgpp/tmp\cccqmssf(.text+0x123):prog.c:undefined referance to 'mysub'
or something similar.

I know I'm probably doing something really dumb but I can't figure it
out!

Thanks,
Alex

Ishpeck wrote:
> 
> It's very simple.  A header file is just a source file with the .h
> extension.  When you import  header, you'll usually go like so:
> 
> #include "header.h"//Notice, it's in quotes, not <> thingies
> 
> If your header is in a different directory as your source file, go like
> this.
> 
> #include "other/dir/header.h"
> 
> Voila!  It's done!
> 
> Inside your header, you might want it all within a special if statement,
> just so you don't over-declare anything.  Like so
> 
> #ifndef __MY_HEADER_NAME__ //The underscores are an arbitrary detail
> #define __MY_HEADER_NAME__
> 
> //Header goes in here:
> //Function prototypes
> //Global variables
> //Constants, etc.
> 
> #endif
> 
> After that, you just treat it like a normal source file.
> 
> Alex Mendes da Costa wrote:
> >
> > Hi All.
> > I know a bit about C programming (i.e. the basics) and wrote a list of C
> > routines that I want to be able to save seperately and then use them in
> > other programs I write. I don't know how to write a header file or
> > invoke the routines with it. Please Help!!
> >
> > Thanks,
> > Alex
> 
> --
> Those who seek enlightenment
> may turn to Ishpeck the wise.
> http://come.to/ishpeck/