hi guys! I want to use boost::interprocess to store some resources (strings) into `bi::map<bi::string, bi::string>` that uses `bi::managed_mapped_file` so I can put the resources in the map once, take the file, and distribute it with the program. the problem is that I cannot calculate the required size in advance, so I want to use `bi::managed_mapped_file::grow ()` before inserting another element into the map. but it doesn't work as i expected, at some point i get exception: what(): boost::interprocess::bad_alloc I know the length of the key string and the length of the value string, how can I find out the size by which I must `grow()` before inserting another element into the map? now my code looks like this: #include <boost/interprocess/managed_mapped_file.hpp> #include <boost/interprocess/allocators/allocator.hpp> #include <boost/interprocess/containers/map.hpp> #include <boost/interprocess/containers/string.hpp> #include <iostream> int main () { namespace bi = boost::interprocess; using segment_manager_t = bi::managed_mapped_file::segment_manager; using void_allocator = bi::allocator<void, segment_manager_t>; using char_allocator = bi::allocator<char, segment_manager_t>; using char_string = bi::basic_string<char, std::char_traits<char>, char_allocator>; using map_value_type = std::pair<const char_string, char_string>; using map_value_type_allocator = bi::allocator<map_value_type, segment_manager_t>; using map_type = bi::map<char_string, char_string, std::less<char_string>, map_value_type_allocator>; static const char *mapfname = "map.dat"; bi::managed_mapped_file mmfile(bi::open_or_create, mapfname, 1024); { void_allocator alloc_inst(mmfile.get_segment_manager()); map_type *mymap = mmfile.find_or_construct<map_type>("MyMap")(alloc_inst); assert(mymap); for ( int i = 0; i < 100; ++i ) { std::string s = std::to_string(i); char_string key(s.c_str(), alloc_inst); char_string value(s.c_str(), alloc_inst); // bi::managed_mapped_file::grow(mapfname, ???); <<<<<<<<<<<<<<<<<<<<<< mymap->emplace(std::move(key), std::move(value)); } } bi::managed_mapped_file::shrink_to_fit(mapfname); return 0; } (or: https://wandbox.org/permlink/jtTOzlMh16ZS8jG6) any ideas? best!