Declare variable as exern if initialized in header?

Posted by Mohit Deshpande on Stack Overflow See other posts from Stack Overflow or by Mohit Deshpande
Published on 2010-04-15T22:29:15Z Indexed on 2010/04/15 22:33 UTC
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header

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source-file

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extern

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c

Say I declare a header file with a variable:

int count;

Then in the source file, I want to use count. Do I have to declare it as:

extern int count

Or can I just use it in my source file? All assuming that I have #include "someheader.h". Or should I just declare it in the source file? What is the difference between putting count in the header file vs the source file? Or does it not matter?

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