Global struct for multiple source files, C

Asked Feb 12 '16 at 04:25

Active Feb 12 '16 at 04:29

Viewed 19 times

I've declared a global structure in supportFunctions.h:

...
struct historyStruct {
    char historyArray[HISTORY_DEPTH][COMMAND_LENGTH];
    int currentSize;
    int totalCommandsExecuted;
};
extern struct historyStruct history;
...

And I've defined history in main.c:

int main(int argc, char* argv[])
{
    struct historyStruct history;
    history.currentSize = 0;
    history.totalCommandsExecuted = 0;
...

historyCommand.c, a file where I want to use history, includes supportFunctions.h but for some reason isn't detecting my global struct history. Whenever I try to use it I'm getting an undefined reference error. Is the process I described the way to create a global struct? Or am I missing something?

asked Feb 12 '16 at 04:25

Adam

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You're declaring a local variable `history` in `main()`, this hides the global variable. – Barmar Feb 12 '16 at 04:28
1

`history` isn't global. It's scope is `main()` – John3136 Feb 12 '16 at 04:28
Where should I declare it? in the header? – Adam Feb 12 '16 at 04:29

Global struct for multiple source files, C

0 Answers0