Re: libio backward compat bug? involving setmntent()

[Zack Weinberg <zack@rabi.columbia.edu>]

On Tue, 13 Apr 1999 08:10:19 -0700 (PDT), H.J. Lu wrote:
>> 
>> On Tue, 13 Apr 1999 07:48:56 -0700 (PDT), H.J. Lu wrote:
>> >> 
>> >> 
>> >> The appended slightly-out-of-spec code segfaults when compiled on a
>> >> libc 2.0 system and run on a libc 2.1 system.  The problem is that
>> >> setmntent() returns a new FILE*, but fclose is bound to the old
>> >> fclose.
>> >> 
>> >> Do we want to support this, and if so, how?  (Have old fclose
>> >> recognize when it's handed a new FILE* and call _IO_new_fclose?)
>> >> 
>> >
>> >Thanks for the bug report. I will fix it.
>> 
>> Try this patch for size.
[...]
>I like this approach. But on the other hand, libio is used
>by both glibc and libstdc++. I am not sure introducing
>_IO_NEW_MAGIC is a good idea or not. As least, you may have
>to change libstdc++ to match it.

I was afraid of that.  I did it this way because I wasn't sure if
there were other functions in libc that return FILE pointers.  Without
this, we'd need versions for all of them.

zw