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On 18 Feb 1999, Alexandre Oliva wrote: > On Feb 18, 1999, Paul Derbyshire <pderbysh@usa.net> wrote: > > > Q: Are STL containers guaranteed to be thread safe? > > No. You must lock them externally. However, it seems to me that the > SGI STL, distributed with egcs, provides some threading support, but > you'd have to check. From what I recall, the -latest- SGI STL is Roughly Threadsafe. You can have multiple threads safely reading a container, but if you plan to write/update/munge a container, no-one else can be reading it. (there really is no way for them to lock some things internally, ie: typedef map<string, string> SSMap; SSMap foo, bar; foo["a"] = bar["a"]; Each half of the assignment would need to lock the container, but what you really need is a lock around the entire statement. Strangely enough, it seems that on Solaris, the Alloc classes aren't threadsafe (or is it just my underlying malloc that's bogus), and I -must- -D_PTHREADS in order for the STL to serialize access to allocations. Elsewise, simple copy-constructoring a container will occasionally segfault. Note though, wrapping that Allocator with a lock gives less-than-stellar performance. Are there plans in 1.1.2 to include the most recent SGI STL? -Bob