[OpenMesh] IO::write - concurrent writing

Dear OpenMesh Devs,

It appears now to me that there is a problem when using IO::write concurrently, from different threads even though these write operations should be independent as they operate on separate meshes and separate streams. When I move the writing operations outside my parallel section, it works fine. When inside the parallel section, I'm getting the double free error quite randomly so I assume that whenever writing is attempted at the same time from multiple threads, it fails. Any idea about why this is happening or any fix would be greatly appreciated.

Thank you, Botond