I read here that, for an input buffer, filebuf::sync's:
effects -if any- depend on the library implementation
So my question then, is can anyone tell me what those effects are for gcc and Visual Studio?
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Jonathan Mee
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@Downvoter Can I get some clarification on the reason for the downvote? – Jonathan Mee Jul 31 '15 at 13:37
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I think it's because the question isn't very clear... for example, do you know that `fflush` is a standard function? – edmz Aug 04 '15 at 11:25
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@black `class basic_filebuf` isn't even standard, but it's Microsoft's behind the scenes implementation of [`filebuf`](http://www.cplusplus.com/reference/fstream/filebuf/). (Incidentally gcc uses the same naming scheme.) – Jonathan Mee Aug 04 '15 at 11:29
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2`basic_filebuf` _is_ standard. – edmz Aug 04 '15 at 11:43
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@black Oh snap you are so right. – Jonathan Mee Aug 04 '15 at 12:01
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GCC's internal implementation of basic_filebuf simply aligns its pbase() and pptr() with the comment:
Make sure that the internal buffer resyncs its idea of file position with the external file.
Visual Studio's internal implementation of basic_filebuf calls fflush(_Myfile) which is not implemented in the header. So it's unclear what that call does. The call is commented with:
synchronize C stream with external file
edmz
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