Subject: Use of TIOCSPGRP in device drivers
To: None <firstname.lastname@example.org>
From: Dave McConnell <email@example.com>
Date: 05/27/1999 14:46:38
I see in the driver code dev/audio.c, the TIOCSPGRP entry to the
audio_ioctl is not used to set the process which may receive a
Instead the "p" argument is used in the FIOASYNC entry (to
audio_ioctl) to record the process that wishes to receive SIGIO's.
Is this correct? I assume its not "incorrect" as it will work.
I believe that the "correct" way for a process to request SIGIO's
from a device is to do an "fcntl" with command F_SETOWN
(translates to a TIOCSPGRP in the drivers ioctl) to identify the
process or group ID wanting the signals, and then to do another
"fcntl" to set the O_ASYNC flag.