Re: [Boost-users] [shmem] error while closing the segment

From: Ion Gaztañaga (igaztanaga_at_[hidden])
Date: 2006-07-10 08:48:52

 > yes, the destructor performs two destroy calls in front of the close 
call (see below). But it should not give a damn about, destroyed is 
destroyed. The call of close should only delete objects that still 
exists. I've printed out the name of the named shared object which 
triggers the error (it's "shmDefinition"). If I comment out the two 
lines which destroy my named shared objects in the destructor, it works. 
Hmm, I don't know why it not work when I destroy the objects by hand. 
But definitely it should not be done twice.

You are right. But this indicates that you somehow have tried to erase 
the same object (in this case ("shmDefinition")) twice (maybe another 
process?). It should assert when using a pointer (because otherwise that 
could corrupt all the segment) when deleting the object (a debug 
protection like when trying to "operator delete" the same ptr two times).

However, when destroying by name, a bool is returned, saying if the 
object has been destroyed or not (well the only problem is to found the 
name in the name-object index). So it should return false in the second 
case, instead of asserting. The only problem is that both name and 
pointer delete operation uses the same code, and only one should assert. 
Thanks for finding this!

Please, erase that assertion from your code. I will do the same in 
Sandbox-CVS, while I find some other solution.

Regards,

Ion