persistent vector

From: michel.andre_at_[hidden]
Date: 2001-07-26 12:46:09

Would there be any interest in an persistent vector with the exact 
same interface as std::vector that stores it's data in a persistent 
file? Preferably implemented using memory mapped files on plattforms 
were they are supported.

Other stl containers could also be adapted to use persistent storage 
in this way.

The proposed interface is that of std::vector only that all 
constructors take a first argument which is a filename for the file 
were the data is stored.

Sample code snippet

{
   mapped_vector<int> vec("sample.dat");
   vec.push_back(1);
   vec.push_back(2);
   vec.push_back(3);
}

{
   mapped_vector<int> vec("sample.dat");
   // vector now contains 1,2,3
   vec.push_back(4);
   vec.push_back(5);
   vec.push_back(6);
}

// vector now contains 1,2,3,4,5,6

I have implemented a test version for Windows NT and i guess a unix 
version could be done using the mmap* family of functions.

Of course there are restrictions on the data contained in such a 
vector it may not contain any dynamically allocated data or pointers.

/Michel