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I have a std::map that I use to map values (field ID's) to a human readable string. This map is initialised once when my program starts before any other threads are started, and after that it is never modified again. Right now, I give every thread its own copy of this (rather large) map but this is obviously inefficient use of memory and it slows program startup. So I was thinking of giving each thread a pointer to the map, but that raises a thread-safety issue. If all I'm doing is reading from the map using the following code: std::string name; //here N is the field id for which I want the human readable name unsigned field_id = N; std::map<unsigned,std::string>::const_iterator map_it; // fields_p is a const std::map<unsigned, std::string>* to the map concerned. // multiple threads will share this. map_it = fields_p->find(field_id); if (map_it != fields_p->end()) { name = map_it->second; } else { name = ""; } Will this work or are there issues with reading a std::map from multiple threads? Note: I'm working with visual studio 2008 currently, but I'd like this to work acros most main STL implementations. Update: Edited code sample for const correctness.

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