Hi.
Is there some one who can tell me how to determine if the CD tray is
open or closed.
My current approach is to simply issue a devctl call, like
DCMD_CAM_CDROMSTART.
I have a feeling there must be a better way.
/Tomas Rosenkvist
Michel Benoit <michel.benoit@saabcom.se> wrote:
Hi.
Is there some one who can tell me how to determine if the CD tray is
open or closed.
My current approach is to simply issue a devctl call, like
DCMD_CAM_CDROMSTART.
I have a feeling there must be a better way.
Take a look at the DCMD_CAM_DEVINFO devctl.
Thank you, that was a cleaner way of doing it, but it is still not good
enough.
The flag field in cam_devinfo_t is always 0x35 or 0x37, DEV_NO_MEDIA goes
on or off.
I can still not see the difference between tray open and tray closed, with
no disc inserted. What I want to know is if the tray is open, not if a
disc is inserted.
Ok ,next issue. Once the tray is inserted I have no problems detecting an
audio cd (sopen("/fs/cd0/.info./audio",…)) but for some reason if the
tray was closed by hand, rather than closed by the eject command, I can
not detect a cd_rom record. I try to do that by calling:
open("/fs/cd0/.info./volume").
I can not even browse the cd from a shell after the tray was closed by
hand and I detect it with the devctl call above, or any other call I have
tried. (I use a timer to make the checking every second while the tray is
open)
What am I missing???
/Tomas Rosenkvist
Kevin Chiles wrote:
Michel Benoit <> michel.benoit@saabcom.se> > wrote:
Hi.Is there some one who can tell me how to determine if the CD tray is
open or closed.
My current approach is to simply issue a devctl call, like
DCMD_CAM_CDROMSTART.
I have a feeling there must be a better way.Take a look at the DCMD_CAM_DEVINFO devctl.
Tomas Rosenkvist <tomasr@sms.se> wrote:
Thank you, that was a cleaner way of doing it, but it is still not good
enough.
The flag field in cam_devinfo_t is always 0x35 or 0x37, DEV_NO_MEDIA goes
on or off.
I can still not see the difference between tray open and tray closed, with
no disc inserted. What I want to know is if the tray is open, not if a
disc is inserted.
There currently isn’t a was to get this information. We are in the process
of adding a CAM pass through interface to the drivers that will allow you
to get this info.
Ok ,next issue. Once the tray is inserted I have no problems detecting an
audio cd (sopen("/fs/cd0/.info./audio",…)) but for some reason if the
tray was closed by hand, rather than closed by the eject command, I can
not detect a cd_rom record. I try to do that by calling:
open("/fs/cd0/.info./volume").
I can not even browse the cd from a shell after the tray was closed by
hand and I detect it with the devctl call above, or any other call I have
tried. (I use a timer to make the checking every second while the tray is
open)
What am I missing???
What is the make/model of the CD-ROM?
Tomas Rosenkvist wrote:
Glad to see someone using the “.info.” entries 
Some minor points
about them, which you may or may not care about …
Ok ,next issue. Once the tray is inserted I have no problems detecting an
audio cd (sopen("/fs/cd0/.info./audio",…))
This may also be a multisession / enhanced audio CD too (in other words,
it has some non-data tracks but may also have data tracks too). But,
you
can definitely play audio from it (“echo play >/fs/cd0/.info./audio”).
I can not detect a cd_rom record. I try to do that by calling:
open("/fs/cd0/.info./volume").
A data CD does not always supply all the information fields in the
primary volume header. By default, entries that are blank/missing
are not shown in the “.info.” filesystem. So you may miss some CDs.
You can force their presence whenever a data CD (as opposed to
audio-only) is inserted by passing the option “cd info=+.info.” to
the filesystem (the leading ‘+’ means always show possible 0-length
entries, a leading ‘-’ means hide such unspecified header fields,
the rest is the name of the pseudo-directory).