How extern can be used?
In which file the variable without extern to be declared?
Or there is no such restrictions?
Any C textbook should be able to explain that.
Extern is used to access global variables/functions that have been declared in another module/file.
In any file. As long as there's no ambiguity.
c-faq.com/.../hfiles.html
c-faq.com/.../extern.html
c-faq.com/.../extarraysize.html
c-faq.com/.../aryptr1.html
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