Re: [boost] [interprocess][Shared memory]

From: Ion Gaztañaga (igaztanaga_at_[hidden])
Date: 2007-03-09 11:22:43

Shibu Bera wrote:
> Hi,
> 
> Thanks Lon for the nice reply. I hope I will get a new method very soon.
> 
> I have one more query about the shared memory.
> 
> I create shared memory using boost::interprocess, at linking time I add
> 
> -lrt -lxml2 -lccext2 -lccgnu2 -ldl (common C++ link library) along with
> 
> -Wall -pedantic -g -pthread -DBOOST_DATE_TIME_NO_LIB
> -DBOOST_INTERPROCESS_POSIX_PROCESS_SHARED -lstdc++ -lboost_thread
> (boost::interprocess link library).

Why do you define BOOST_INTERPROCESS_POSIX_PROCESS_SHARED? This is an 
internal define that will be generated if Interprocess can detect POSIX 
process-shared mutexes. Otherwise, if you are using gcc, atomic 
operations would be used. Which system are you using, Linux?

> The common C++ library is added for the other requirement of the
> application.
> 
> I open the shared memory form the another process, where "comman C++ link
> library" is not added. Segmentation fault is the result.
> 
> Then I created two shared memory.
> First with "common C++ link library" and "boost::interprocess link library"
> And
> Second with only "boost::interprocess link library",
> 
> These two shared memories are different, I found offset of some bytes on the
> actual values stored in the shared memory. I am not finding the way, why
> this problem is. I want to know how any other link libray may change the
> data of the shared memory. Please help.

Sorry, I can't understand your problem properly. Linking another library 
is not important to use Interprocess. Can you elaborate a bit more? 
Please remove the define I mentioned before, because otherwise you might 
have problems.

Regards,

Ion