Device Emulation with a pty?

[Guy Harris]

>>  * detect device specific slave side ioctls and reply to them from
>>    the master side.
>
>Look up TIOCPKT and TIOCREMOTE.

Which will tell you that you can only detect *some* effects from
slave-side "ioctl"s (I'm not sure what "reply to them from the master
side" means, but if it means that the process on the master side is to
be responsible for providing the return code for "ioctl"s or providing
the return data from "ioctl"s such as TIOCGETP that return data, you
can't do that, either).