Le mercredi 27 avril 2011 à 14:37 +0800, Lifeng Sun a écrit :

On 07:58 Wed 04/27/11 Apr, Eric Dumazet wrote:

quoted

Really ?

EINVAL is ok too : Request or argp is not valid.

I'm afraid not. SUSv4 specifies, say,

  int tcsetattr(int fildes, int optional_actions,
         const struct termios *termios_p);

 ERROR:
  [EINVAL]
      The optional_actions argument is not a supported value, or an
      attempt was made to change an attribute represented in the
      termios structure to an unsupported value.

  [ENOTTY]
      The file associated with fildes is not a terminal.

which means when we apply tcsetattr (implemented by ioctl) to _any_
non-terminal file descriptor, it should set errno to ENOTTY rather
than EINVAL.

You quote manpage for a library call, not a system call.

If you feel your glibc doesnt implement well this, please complain to
glibc maintainer.