Re: share a variable across two libraries
On Jun 25, 9:28 am, guddu <visha...@gmail.com> wrote:
I have to share a variable across two libraries. These libraries are
build separately and share a common header file.
I had tried this earlier using extern variable. That didn't help.
Any ideas about this ??
You can do that using your platform specific facilities.
One way is to put that variable in a shared library (.so or .dll)
which both users of that shared variable link against. The run-time
linker will load the shared library only once, so that this variable
get shared between all users of that variable (provided they are in
the same process).
The other way is to store the shared variable in a named memory
mapping. The mapping may be reference counted, so that it is created
on the first use and destroyed when the last user has done with it.
This way there is no need for shared libraries, however, the users
still need to share the definition of that variable and the name of
the memory mapping through a header file.
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