Re: [regression] ENOTTY returned for tty fds

[Herbert Xu]

On Wed, Jul 24, 2024 at 06:53:00PM +0800, Herbert Xu wrote:
> On Wed, Jul 24, 2024 at 12:15:39PM +0200, Greg KH wrote:
> >
> > -ENOTTY is the documented result of invalid ioctl arguments sent, I am
> > pretty sure POSIX requires this somewhere.  So this was fixing a
> > requirement here...
> 
> POSIX does not specify this at all:
> 
> https://pubs.opengroup.org/onlinepubs/9699919799/functions/ioctl.html

In fact it says:

If an underlying device driver detects an error, then ioctl() shall fail if:

[EINVAL]
The request or arg argument is not valid for this device.

[ENOTTY]
The file associated with the fildes argument is not a STREAMS device that accepts control functions.

Of course this is all moot since POSIX only specifies ioctl(2)
for STREAMS devices, but this patch in question is literally
going against the woring here.

Cheers,
-- 
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
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