Re: external variables

On Wed, 11 Feb 2009 18:10:07 -0800, Keith Thompson wrote:

Larry Gates <larry@xxxxxxxxxxxxxxx> writes:
On Tue, 10 Feb 2009 07:54:55 -0500, pete wrote:
Also, you can have a declaration with the extern keyword
inside of a function definition.

Well, if you can't declare a function from within a function, what use is
the keyword extern going to do you there?

You can't *define* a function within a function definition:

void outer(void) {
void inner(void) { } /* ILLEGAL */
}

You can *declare* a function within a function definition:

void func(void) {
extern void external_function(void); /* OK */
}

but it's no necessarily a good idea. Normally function declarations
like this (prototypes) should be in header files, not buried inside
function definitions.

And that extern is necessary there?
--
larry gates

Perl itself is usually pretty good about telling you what you shouldn't
do. :-)
-- Larry Wall in <11091@xxxxxxxxxxxxxxxxxxxxxxx>
.

Relevant Pages

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