Can I use a FILE* to initialize a C++ ostream object?

Can I use an elsewhere opened

FILE* f = ...

thing to initialize some std::ostream instance? Like this (pseudocode):

FILE *f = ...;
std::ostream os;
os./*bind_to_f*/( f );   开发者_如何学Python // HOW?
os << "Hello world" << std::endl;

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FILE* and streams are C and C++ style I/O capabilities respectively. Since the C++ library doesn't always know about the implementation of the underlying C library there's no way to do this. Additionally consider, what would the ownership semantics be if you could do this?

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With GCC you can just pass the existing file descriptor to the constructor (ref):

FILE *f = ...;
std::ofstream os(fileno(f));

Constructor: ofstream::ofstream (int fd)

Make an ofstream for writing to a file that was already open, using file descriptor fd.

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If you were to create a streambuf class that used a FILE* internally, you could do it. For example, HP OpenVMS seems to have a class like that.