Support Requests item #1445474, was opened at 2006-03-08 01:03 Message generated for change (Tracker Item Submitted) made by Item Submitter You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=207586&aid=1445474&group_id=7586 Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: None Group: None Status: Open Resolution: None Priority: 5 Submitted By: Nobody/Anonymous (nobody) Assigned to: Nobody/Anonymous (nobody) Summary: boost.iostreams file_descriptor and sharing Initial Comment: Hi! I have couple of questions about the behavior of boost::iostreams::file_descriptor. First, I've noticed that it always opens files with exclusive access. That is, it calls CreateFileA with a dwShareMode of 0, which means that "the object cannot be shared and cannot be opened again until the handle is closed". Is this by design? Wouldn't it be reasonable to use a share mode of FILE_SHARE_READ when opening a file only for reading? Second, the function file_descriptor::open has a third parameter 'base', which appears to be extra open mode bits that are always on, in addition to those in the second parameter to stream::open. What is the purpose of this? Since there is a stream::open function with three parameters I can specify these extra bits as well when opening the file, in order to actually get the file opened only for reading, but I worry that this will somehow violate the design of the file_descriptor class. I've modified my copy of file_descriptor::open to use a share mode of FILE_SHARE_READ when opening a file only for reading and am now calling stream::open with three arguments in order to make this happen. Is this safe? It appears to work in the very limited cases I've tried so far. Yours, Gunnar Blomberg (Gunnar.Blomberg@iar.se) PS. Thanks for an excellent library! DS. ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=207586&aid=1445474&group_id=7586 ------------------------------------------------------- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnk&kid=110944&bid=241720&dat=121642 _______________________________________________ Boost-bugs mailing list Boost-bugs@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/boost-bugs