Hi to all, I open this discussion as a "branch" of "[BGL] Multithread problem inserting edges and exploring the same graph". Can someone tell me if the PBGL and MTGL can help me? I report my problem below, for sake of comfort. Thanks in advance, Cosimo Calabrese. ************************************************** I've a problem on BGL. My environment is WinXP, Visual Studio 2005, Boost 1.37. I'm trying to use BGL in the following way. I've a single graph in my application, that is an adjacency_list< vecS, vecS, ... >, and I've 2 kind of threads that work on the graph: - some "Explorer" threads, that executes a Dijkstra's algorithm repeatedly; - some "Integrator" thread, that call the add_edge() function repeatedly. The program often crashes, because it cannot dereference some graph elements, some auto_ptr... The crash isn't sistematic, so I think there's a concurrency problem. [...] **************************************************