Re: filebuf::fd()

[Gabriel Dos Reis <gdr at codesourcery dot com>]

Phil Edwards <pedwards@disaster.jaj.com> writes:

| I'd really like for us to decide on a way to conditionalize these extensions
| (e.g., my posting on 29 Sept, item #2).
| 
| Anyhow, by popular-and-IMHO-slightly-misguided demand, here's a way for
| filebuf's to return an underlying file descriptor, for the currently
| default --enable-cstdio=stdio case.  I did not investigate the libio case.
| 
| Also some cleanups:
|     1)  for is_open, make it clear that we're comparing pointers.

Well, I think the code was clear as written, and I don't think the
change is necessary.

|     2)  for the testcase file, when our non-standard signature was changed,
|         the comment was not.  Also <cassert> is included in the hooks header.
| 
| Opinions?

Recent discussions ont the LWG list make me nervous about adding
extensions, but hey we have to deal with some users requests.

I discussed the issue with Theo two weeks ago.  I think returning a
FILE* would be self-contained in terms of semantics.  That is, isntead
of retuning an int (the file descriptor), have a member function --
say FILE_pointer() -- return a FILE*.  That scheme is extensible to
libio.
|    template<typename _CharT>
|      bool 
| -    __basic_file<_CharT>::is_open() { return _M_cfile != 0; }

This change is uncessary.

| +      int 
| +      fd();
| +

Replace this with

+   #ifdef _GLIBCPP_USE_EXTENSIONS
+      FILE*
+      FILE_pointer();
+   #endif

-- Gaby