bison I/O error

[ENTRESSANGLE ERIC]

Hello

I'm getting the following error using bison 2.3 :

Building Unsupported.tab.c because it does not exist.
bison -d -pUnsupported  Unsupported.y
bison: I/O error
gmake: *** [Unsupported.tab.c] Error 1
or38 linus>bison -V
bison (GNU Bison) 2.3

Any clue about what might be the root cause of the problem ?

Thanks a lot

Eric