Re: Linker error multiple definitions

From: E. Robert Tisdale (E.Robert.Tisdale_at_jpl.nasa.gov)
Date: 11/18/03 

Date: Tue, 18 Nov 2003 08:29:53 -0800

Andrew wrote:

> I am receiving a multiple definition error from the linker
> when I try to build a project I am working on.
> The message states that the functions I that defined
> within an external .c source file are already defined
> in the main program .obj file.
> I declared the functions in separate header files

Are you sure that you didn't actually *define* the function
in the header files?

> and used the pre-processor conditional #ifndef FILE_H
> to make sure each header is only included once.

But your compiler isn't complaining about multiple *declarations*.
It is complaining about multiple *definitions*.
You can *declare* a function multiple times
but it should only be *defined* once.

> Each .c source file includes the associated header as does the
> main .c file which calls the functions. I know I have done this before
> without any problems, but am I missing a step? Thanks for any help.

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