Re: [PATCH liburing] man/io_uring_enter.2: add notes about direct open/accept

[Pavel Begunkov <asml.silence@gmail.com>]

On 8/31/21 9:04 PM, Jens Axboe wrote:
> On 8/31/21 1:52 PM, Pavel Begunkov wrote:
>> Add a few lines describing openat/openat2/accept bypassing normal file
>> tables and installing files right into the fixed file table.
>>
>> Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
>> ---
>>  man/io_uring_enter.2 | 36 ++++++++++++++++++++++++++++++++++++
>>  1 file changed, 36 insertions(+)
>>
>> diff --git a/man/io_uring_enter.2 b/man/io_uring_enter.2
>> index 9ccedef..52a5e13 100644
>> --- a/man/io_uring_enter.2
>> +++ b/man/io_uring_enter.2
>> @@ -511,6 +511,18 @@ field. See also
>>  .BR accept4(2)
>>  for the general description of the related system call. Available since 5.5.
>>  
>> +If the
>> +.I file_index
>> +field is set to a non-negative number, the file won't be installed into the
>> +normal file table as usual but will be placed into the fixed file table at index
>> +.I file_index - 1.
>> +In this case, instead of returning a file descriptor, the result will contain
>> +0 on success or an error. If there is already a file registered at this index,
> 
> I don't think non-negative is correct, it has to be set to a positive
> number. non-negative would include 0, which isn't correct.

Oh, right, should have been non-zero

> Should also include a note on if these types of file are used, they
> won't work in anything but io_uring. That's obvious to us, but should be
> noted that they then only live within the realm of the ring itself, not
> the system as a whole.

Will send a v2


-- 
Pavel Begunkov