mmap stdio breaks GNU ld

[Ulrich Drepper]

Mark Brown <bmark@us.ibm.com> writes:

> Here is a quote from ISO C 99:

ISO C cannot possibly talk about file descriptors.  The wording used
"file position indicator" refers to the possibly abstract position in
the file which is maintained by computations of the buffer pointer and
possibly an offset variable:

   +-----------------------------------------------------------------+
   |                                                                 |
   +-----------------------------------------------------------------+
   ^                           ^                                     ^
   |                           |                                     |
   readstart             readptr                               readend

Given this the file position if computed as

  offset - (readend - readptr)

where 'offset' is the offset of the byte following the last byte in
the buffer.  'offset' can also be the actual file descriptor position.
And note, this was always in the case even with the file descriptor
not being at the beginning of the file.

The only standard which could talk about file descriptors is
Unix/POSIX and the fopen man page says nothing.

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