Photo-card access details and troubleshooting
This file provides more detailed information about
setting up photo-card access with the hpoj
software, including possible troubleshooting steps in case something goes
Additional information may be found in the separate document pertaining to
Also, be sure to consult the connectivity
details and troubleshooting document, because some issues here may
actually be connectivity-related.
General photo-card issues
Problem: I inserted a photo card, and the device asked me if I wanted
to save photos to my PC. I selected "Yes", but nothing happened.
This method of saving photos to your PC is not currently supported by
the hpoj software. Use the
Question: I want to copy files from one type of photo card to another.
Can I insert both cards and do a direct copy?
No. Even though your device may have multiple slots for different card
types, only one card may be inserted and accessed at a time.
If you want to copy files from one card to another, then you can copy
them to your hard disk as an intermediate step. Alternatively, if you
have more than one hpoj-supported device with card readers, then each
one can have its own
drive letter and/or USB-mass-storage mount point, and you can copy
from one drive letter directly to another using a single mcopy
or cp command, depending on which photo-card-access protocol(s)
each device support.
Question: Can I use gPhoto with
Question: My PSC 2510 supports "Instant Share" over the integrated network
interfaces (10/100T ethernet and 802.11 wireless). Can I use this from
Question: What is the significance of the the X-Windows-style "display
numbers" specified in /etc/mtools.conf or ~/.mtoolsrc?
The original intention behind
"remote" feature was that
you could run floppyd (the floppy-disk-drive daemon) on your local
system, log into a remote system, set your DISPLAY back to your
local system for purposes of running remote X-Windows applications, and use
commands on the remote system to access the floppy
drive (for example) on your local system. Typically you would be using
a single drive in this manner and using display number ":0" on
your local system. For security purposes, the remote
instance would look for X authentication information for the display
name/number corresponding to the remote drive letter, and pass that back
to the local floppyd instance, which would validate it before
granting remote access to the drive.
The hpoj ptal-photod-based photo-card
access method stretches somewhat this floppyd concept. In this
case, the user is presumed to be logged into the same local system on which
ptal-photod is running, and it's
possible to have more than one photo-card-capable device. As a result,
the "display name/number" specified in /etc/mtools.conf or
~/.mtoolsrc doesn't necessarily have anything to do with that of
the X server or the DISPLAY environment variable, but is merely
used to connect a particular
drive letter to a particular
instance of ptal-photod. However,
due to the
historical bias towards the original
X-Windows-based floppyd concept, the
client utilities still expect to find something that looks like an X
authentication token for the drive letter's "display name/number", even though
ptal-photod makes no use of it.
Problem: I got an "authentication failed" error message.
command gives an error message such as:
Permission denied, authentication failed!
Auth failed: X-Cookie doesn't match!
Can't open :2: No such file or directory
Cannot initialize 'R:'
then try running the following command:
xauth add :2 . 00
Substitute for ":2" the display name/number specified in
/etc/mtools.conf or ~/.mtoolsrc which is being
Caution: Don't do this otherwise (i.e. on an display name/number
on which you have an active X session), or you may break your X session.
requires an xauth token in
order to connect to ptal-photod,
ptal-photod ignores any authentication
information passed to it. Therefore, it's not actually necessary to be
running X Windows on the specified display name/number, or even at all, as long
can find an xauth token (valid or not) for the
specified display name/number in the user's .Xauthority file.
Problem: I can't access the photo-card readers on the OfficeJet D
or 7100 series through an LIO JetDirect.
ptal-photod doesn't work with the
OfficeJet D or 7100 series via an LIO JetDirect connection. This is a
limitation in the device, not
ptal-photod or the LIO JetDirect.
Use a parallel or USB connection instead, which can be connected either
directly to your computer or to an hpoj-supported external JetDirect print
server. Note that with the OfficeJet D and 7100 series, you can still
otherwise use your LIO JetDirect even if you're also using the USB port.
Question: How can I make ptal-photod
accessible to other computers on the network?
Add the ptal-photod -bindto or
-bindtoall switch to the "init.photod.append+=" line in the
device configuration file in /etc/ptal,
but make sure you have an appropriate firewall set up to prevent access by
untrusted clients. Then change /etc/mtools.conf or
~/.mtoolsrc to use something like file="other.machine.com:0"
and try it out (this hasn't been tested as of the time of this writing).
Question: Do I really need to set "mtools_skip_check=1"?
The "mtools_skip_check=1" line is needed for photo cards formatted
with certain digital cameras and relaxes some of
sanity checks on the photo-card's file system. It's safe to remove it if it
turns out you don't need it for your photo card(s).
Question: How do I format a brand-new photo card so
can access it?
It is recommended to format it using your digital camera if possible.
There is an mformat command which might work, but this has
not been tested, so proceed with caution. If you do try it, then
let us know on the
mailing list if it worked or not.
-based photo-card access is slow.
- If using parallel, try switching to USB if possible.
- If using parallel, make sure your parallel port is set to ECP if possible.
- If your device supports it, try using the USB mass-storage interface method.
- Try using the "mcopy -b" switch, but beware that this switch
may increase the chance of data corruption if something goes wrong while
writing to the photo card.
Question: Why can't I just mount the photo card as a file system and
use standard Unix file-manipulation commands?
That would require writing a non-portable kernel-mode block-device driver,
which would be complicated by the fact that it would have to access a
user-mode I/O protocol stack (libptal,
There is also
(Framework for User-Space Devices). Currently it only supports
proxying of character devices. Once FUSD is able to proxy block
devices, it may be possible to add FUSD support to
ptal-photod and allow photo cards to
be mounted as a file system.
It might be possibile to develop a kernel-mode block-device driver that
"floppyd" client network protocol
to talk to ptal-photod, assuming
it's possible to use TCP/IP client sockets from kernel space.
On the other hand, if your device also provides a standard USB mass-storage
interface, you can mount that as a file
Question: Are HP PhotoSmart cameras supported using
No. Some PhotoSmart cameras work using a standard USB mass-storage
interface, where you can mount the photo card as a file system.
Others work using gPhoto, using
a PTP (Picture Transfer Protocol) or other backend driver.
Others may not work with Linux at all.
USB mass storage - specific issues
Problem: The mount command failed for my device with a USB
If the mount command fails, then try it again 2-3 more times.
If that doesn't help, try mounting the device node /dev/sda
(without the "1") once, which will probably fail, and then go
back to trying /dev/sda1 one more time.
Or on a system with devfs (a dynamic /dev file system)
enabled, if all else fails look at the /dev/sd* device nodes,
which are probably symlinks into the /dev/scsi tree, search
through the /dev/scsi tree for part* (partition) block
device nodes (possibly with a command such as "find /dev/scsi -type
b"), and try mounting the appropriate block device there.
Question: My device has a USB mass-storage interface but is connected
to a USB JetDirect print server. Can I somehow use the USB mass-storage
interface over the network?
No. Try using the
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