static extern?

[Gernot Frisch]

Problem:

A.cpp:
------
static FOO* gFoo=NULL;

A.h
extern FOO* gFoo;

gives: L2001 - unresolved external: "symbol struct FOO* gFoo"

if A.h looks like:
extern static FOO* gFoo;

it gives:
C2159: more than one storage class specified.

<blink, blink>
How would I do this now? I have a prefedined macro that makes a
"static FOO*". And I want to tell all my other .cpp files that it
exists in stdafx.h.

Thank you,
--
-Gernot
int main(int argc, char** argv) {printf
("%silto%c%cf%c gl%ssic%ccom%c" , "ma", 58, 'g', 64, "ba", 46, 10);}

_______________ _______________ __________
Looking for a good game? Do it yourself!
GLBasic - you can do
www.GLBasic.com

[Vince Yuan]

Try this:

A.h
static FOO* gFoo;

A.cpp:
extern static FOO* gFoo=NULL;

Vince

"Gernot Frisch" <[e-mail] > wrote in message
news:2k******** *****@uni-berlin.de...

Problem:

A.cpp:
------
static FOO* gFoo=NULL;

A.h
extern FOO* gFoo;

gives: L2001 - unresolved external: "symbol struct FOO* gFoo"

if A.h looks like:
extern static FOO* gFoo;

it gives:
C2159: more than one storage class specified.

<blink, blink>
How would I do this now? I have a prefedined macro that makes a
"static FOO*". And I want to tell all my other .cpp files that it
exists in stdafx.h.

Thank you,
--
-Gernot
int main(int argc, char** argv) {printf
("%silto%c%cf%c gl%ssic%ccom%c" , "ma", 58, 'g', 64, "ba", 46, 10);}

_______________ _______________ __________
Looking for a good game? Do it yourself!
GLBasic - you can do
www.GLBasic.com

[Mark Warren]

Gernot Frisch wrote:

Problem:

A.cpp:
------
static FOO* gFoo=NULL;

A.h
extern FOO* gFoo;

gives: L2001 - unresolved external: "symbol struct FOO* gFoo"

if A.h looks like:
extern static FOO* gFoo;

it gives:
C2159: more than one storage class specified.
Yes, the variable gFoo cannot be static and extern at the same time.
<blink, blink>
How would I do this now? I have a prefedined macro that makes a
"static FOO*". And I want to tell all my other .cpp files that it
exists in stdafx.h.

Thank you,

Solution:

A.cpp:
------
FOO* gFoo=NULL; // Note no static

A.h
----
extern FOO* gFoo;
HTH

Mark

[Gernot Frisch]

> Solution:

A.cpp:
------
FOO* gFoo=NULL; // Note no static

A.h
----
extern FOO* gFoo;

I rewrote the code so I can do this now. But I don't understand it.
Why can't I tell another .cpp file that there is an static variable
somewhere else?
-Gernot

[Sharad Kala]

"Gernot Frisch" <[e-mail] > wrote in message
news:2k******** *****@uni-berlin.de...

Solution:

I rewrote the code so I can do this now. But I don't understand it.
Why can't I tell another .cpp file that there is an static variable
somewhere else?

Because static variables having namespace scope have internal linkage i.e.
the entity it denotes can be referred to by names from other scopes in the
same translation unit only.

[Rolf Magnus]

Gernot Frisch wrote:

Problem:

A.cpp:
------
static FOO* gFoo=NULL;

A.h
extern FOO* gFoo;

gives: L2001 - unresolved external: "symbol struct FOO* gFoo"
Well, static means internal linkage, extern means external linkage. You
have to choose one. If the variable is static, it doesn't make much
sense to declare it as extern in the header.
if A.h looks like:
extern static FOO* gFoo;

it gives:
C2159: more than one storage class specified.

<blink, blink>
How would I do this now? I have a prefedined macro that makes a
"static FOO*". And I want to tell all my other .cpp files that it
exists in stdafx.h.

Why? It's static, so it doesn't exist outside of the .cpp file where
it's defined.

[Gernot Frisch]

> Why? It's static, so it doesn't exist outside of the .cpp file where

it's defined.

Because: That is exactly what I didn't know. :) Thank you,
Gernot

[Andrey Tarasevich]

Gernot Frisch wrote:

...
Why can't I tell another .cpp file that there is an static variable
somewhere else?

Because that what this particular use of 'static' is intended to do in
the first place! It is intended to make the variable "invisible" from
other translation units. If you want to be able to link to that variable
from other translation units - give it external linkage.

--
Best regards,
Andrey Tarasevich

[Jack Klein]

On Mon, 28 Jun 2004 17:53:22 +0800, "Vince Yuan" <sh*******@citi z.net>
wrote in comp.lang.c++:

First, don't top post.

Try this:

A.h
static FOO* gFoo;

A.cpp:
extern static FOO* gFoo=NULL;

Vince

Second, this is complete nonsense.

--
Jack Klein
Home: http://JK-Technology.Com
FAQs for
comp.lang.c http://www.eskimo.com/~scs/C-faq/top.html
comp.lang.c++ http://www.parashift.com/c++-faq-lite/
alt.comp.lang.l earn.c-c++
http://www.contrib.andrew.cmu.edu/~a...FAQ-acllc.html

[Howard]

"Rolf Magnus" <ra******@t-online.de> wrote in message
news:cb******** *****@news.t-online.com...

Gernot Frisch wrote:

Problem:

A.cpp:
------
static FOO* gFoo=NULL;

A.h
extern FOO* gFoo;

gives: L2001 - unresolved external: "symbol struct FOO* gFoo"

Well, static means internal linkage, extern means external linkage. You
have to choose one. If the variable is static, it doesn't make much
sense to declare it as extern in the header.

<rant>

You know, I can't for the life of me figure out why "static" was used to
mean internal linkage in this case. I'd think "intern" or something similar
would be much more logical, and simply eliminate the use of "static" for
non-member functions and variables. I know this is not the forum for asking
"why", but it really bugs me to have a keyword that has no apparent relation
to its use. One would think that "static" should have the same (or at least
similar) meaning in this context as it does in member functions and
variables. And since it makes no sense to try to apply the same meaning in
this case as in the member (or local variable) case, it really just
shouldn't exist at all here. "But that's just my opinion...I could be
wrong."

</rant>

-Howard