[Insight-developers] fail() fails on the Mac

[Luis Ibanez]

Hi,

Tracking some failing IO test on the Mac,
we ran again into the problem with the
Mac's broken implementation of

     fstream.fail()
     fstream.eof()

Whenver you read the last N bytes of a
file, the Mac is returning true in
fail() and eof(). This should only happen
if you try to read N+1 (or more).

Many of the ImageIO classes are using
fail() for testing their reads. Since
the solution involves to use #ifdefs
for APPLE that make the code less readable,
a new method

        ReadBufferAsBinary()

was added at the level of the ImageIOBase

The method is to be used as


    if( !ReadBufferAsBinary( ifstream, myBuffer, numberOfBytes ) )
      {
      // error during reading
      }

It checks internally whether the expected
number of bytes has been read or not.
The internal test is Mac-resistant.


Please take this method into account when
writing new ImageIO classes or when modifying
the existing ones.



   Luis