Declaration Vs Definition of variable

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What is the difference between the "Declaration" and "Definition" of variables in terms of different storage class?

Posted 27-Apr-11 19:20pm

vishal_kapoor

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Sergey Alexandrovich Kryukov · Accepted Answer · 2011-04-27T19:47:00

Solution 2

For explanation, look here:
http://en.wikipedia.org/wiki/External_variable[^].

For a sample, locate the section "Example (C programming language)"; file1 — definition; file2 — declaration. Usually declaration is used in *.h file, so there are many repetitions of the text of the same declaration in the same project, but the definition should be only one (otherwise the symbolic linker won't be able to resolve which one to use), so the definition is placed only once in some *.C file.

—SA

Posted 27-Apr-11 19:47pm

Sergey Alexandrovich Kryukov

Comments

vishal_kapoor 28-Apr-11 2:29am

extern variable is "declaration without definition". What about the other storage class variables like auto, register, static? Others are declaration and definition both at the same time?

Sergey Alexandrovich Kryukov 28-Apr-11 2:38am

Everything else is unrelated to this dilemma, only extern. Learn them separately.
With functions -- declaration is a function without body.
--SA

Albin Abel 28-Apr-11 23:44pm

My 5.

Sergey Alexandrovich Kryukov 28-Apr-11 23:57pm

Thank you, Albin.
--SA