列出Boost命名的托管共享内存的名称

Question

I am using boost managed_shared_memory. And I am creating by name.

Eg: managed_shared_memory Segment(open_only, OneName);

And inside in an own segment I can list all existing objects (created by Segment::construct).

But is it possible to get a list of existing segments? (Eg to avoid double naming...)

Such like (Pseudo):

boost::interprocess::list_existing_segments 

If it is possible, please explain. If not, be so kind to confirm.

Greeting Earlybite

Answer 1

But is it possible to get a list of existing segments?

Given enough privileges, probably yes. However, that's not where Boost focuses (use tools like Process Explorer to inspect system details; on linux, ls /dev/shm usually helps). ¹

(Eg to avoid double naming...)

That's not viable, as at this point you'd only get a race. As soon as you "established" that a given name is not in use yet, it might simultaneously be created by one of the many other processes in the system. So the result of your check is useless.

You cannot hedge this by interprocess synchronization, because (catch-22) the same problem applies to the synchronization object used for that.

In short: You can only try the creation and notice that it failed.

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¹ Likewise, Boost doesn't focus on lowlevel hardware access, instead abstracting a higher level interface that's portable