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Global variables

Posted on 1998-07-22
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Last Modified: 2010-04-15
I have the following declaration in the header file of my project. This header file is included in every source file of the project. At one point in my main routine, I set this pointer to an address. After that, I start a series of threads that use the pointer. The problem is, some of the routines I call don't show the value I set prior to calling them but instead show NULL (the pointer's compile time value). What's wrong?

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static struct CONNLIST *pProcessList = NULL;
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Question by:flfmdll
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yonat earned 20 total points
ID: 1251781
"static" means file scope. So there is a separate pProcessList for each file that #includes this header. Replace "static" with "extern" in the header:
    extern struct CONNLIST *pProcessList;
and define the variable in just *one* of your .c files:
    struct CONNLIST *pProcessList = NULL;

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Author Comment

by:flfmdll
ID: 1251782
Thank you. That works just fine. My excuse: it's been a very long time since I have used global variables.
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