Antoine:

I'm not sure what the expected behaviour should be either, this is certainly for others more familiar with Python than I to decide.  Although I am certainly annoyed that the current behaviour differs between Solaris and Linux.  Haven't had time to check other platforms to see how things should be.

Also, the behaviour seems inconsistent between the various file methods on Solaris which seems wrong.  Finally, from looking into fileobject.c, clearerr() is used in most places and the omissions (corrected by my patch) do seem unintentional to me, e.g. bugs.

Hope this helps.