on Fri, 24 Feb 2023 08:34:14 -0500 you (Rich Felker ) wrote: > Is there any indication that passing NULL as the first argument to > fread is not itself undefined? Normally I would expect that to be the > case. I don't think so. The corresponding text of the C standard clearly indicates that the first argument is expected to point to an array. By that the provisions of 7.1.4 take effect: If an argument to a function has an invalid value (such as ..., or a null pointer, ...) ..., the behavior is undefined. Thanks Jₑₙₛ -- :: ICube :::::::::::::::::::::::::::::: deputy director :: :: Université de Strasbourg :::::::::::::::::::::: ICPS :: :: INRIA Nancy Grand Est :::::::::::::::::::::::: Camus :: :: :::::::::::::::::::::::::::::::::::: ☎ +33 368854536 :: :: https://icube-icps.unistra.fr/index.php/Jens_Gustedt ::