hpoj reference: `ptal-photod`

The ptal-photod daemon implements the mtools "floppyd" network protocol. Its purpose is to let you use mtools as a portable method for reading and writing files on photo cards inserted in hpoj-supported multi-function peripherals. Such photo cards are normally formatted with an MS-DOS FAT or VFAT file system.

Click here for more information on setting up photo-card access with the hpoj software.

Syntax

The ptal-photod command-line syntax is as follows:

	ptal-photod devname [options...]

Where:

devname is the PTAL device name (required)

Recommended options: one (but usually not both) of the following:

-maxaltports n -- tries up to n (for example, 26) successive TCP/IP ports if the desired or default TCP/IP port address is already in use, presumably by another ptal-photod or floppyd instance
-portoffset n -- the desired TCP/IP port offset (default=0) relative to the TCP/IP base port (see -baseport below)

Other possible options (not necessary in most cases):

-bindto IPaddress -- binds to specified TCP/IP address (default=127.0.0.1)
-bindtoall -- binds to all TCP/IP interfaces
-baseport n -- sets TCP/IP base port (default=5703)
-tcpport n -- binds to TCP/IP port n (default=baseport+portoffset)
-readonly -- disables writes
-readwrite -- enables writes (default)
-nofork -- runs in foreground (default is background daemon)

Notes

ptal-photod logs startup and error messages to syslog (/var/log/messages) in addition to logging to standard error.
ptal-photod currently only supports photo cards which were formatted with 512 bytes per sector.
ptal-photod is somewhat slow, especially on older models, because it currently reads/writes only one sector at a time when presented with a multiple-sector request from mtools.
The floppyd protocol was originally designed for accessing local floppy drives from a remote system you have logged into and set your X-Windows display back to your local system. As a consequence, mtools expects to find "X cookie" authentication information for each X display number which corresponds to a remote drive, even though ptal-photod doesn't use this information. If mtools gives some sort of "authentication failed" error message with a given drive letter (for example, R:) and display number (for example, ":2"), then run the command "xauth add :2 . 00", substituting the correct display number in place of ":2".
If you use the -bindto or -bindtoall options to make the device's card-reader functionality available to other network clients, then be careful to set up an appropriate firewall to prevent untrusted clients (such as on the public Internet) from accessing this service.
If your device provides a standard USB mass-storage interface, you may get better performance and usability if you use that access method instead of mtools and ptal-photod, because it allows you to mount the card as a VFAT file system and use a wide variety of Linux/Unix file-management tools.
If you kill and restart ptal-photod (presumably via "ptal-init start") too quickly, then sometimes ptal-photod is restarted before the old instance's TCP port is fully released, which may cause the new instance to use a different TCP port, which will map to a different drive letter, or to fail to start altogether. As a workaround, "ptal-init start" delays before starting the first instance of ptal-photod, but if this isn't enough and this problem still occurs for you, then consider splitting the "restart" operation into separate "stop" and "start" steps to give extra time for the TCP port to get fully released.

Examples

Given the following lines in /etc/mtools.conf (for all users) or ~/.mtoolsrc (for specific users):

        drive p: file=":0" remote
        drive q: file=":1" remote
        drive r: file=":2" remote

The mtools drive P: will be mapped to port 5703 on the local system, drive Q: will be mapped to port 5704, and drive R: will be mapped to port 5705.

If you start ptal-photod as follows:
```
	ptal-photod mlc:usb:PSC_900_Series -maxaltports 26
	ptal-photod mlc:usb:PHOTOSMART_100 -maxaltports 26
```
then mlc:usb:PSC_900_Series will be bound to port 5703 and therefore drive P:, and mlc:usb:PHOTOSMART_100 will be bound to port 5704 and therefore drive Q:, because of the order in which the two instances of ptal-photod are started. Drive R: will not have anything bound to it.
If you start ptal-photod as follows:
```
	ptal-photod mlc:usb:PSC_900_Series -portoffset 1
	ptal-photod mlc:usb:PHOTOSMART_100 -portoffset 0
	ptal-photod mlc:usb:officejet_d_series -portoffset 1	# Will fail.
```
then mlc:usb:PSC_900_Series will be bound to port 5704 and therefore drive Q:, and mlc:usb:PHOTOSMART_100 will be bound to port 5703 and therefore drive P:, because specific port offsets relative to port 5703 were specified. However, the above invocation for mlc:usb:officejet_d_series will fail, because the "-portoffset 1" switch conflicts with that of mlc:usb:PSC_900_Series. In order to safeguard against failures due to inadvertently specifying the same -portoffset twice, you can still also specify something like "-maxaltports 26", which would have made mlc:usb:officejet_d_series roll over to port 5705 and therefore drive R:.

hpoj reference: ptal-photod

Syntax

Notes

Examples

hpoj reference: `ptal-photod`