Provided by: hpoj_0.91-9_i386 bug

NAME

       hpoj reference: "ptal-init"

DESCRIPTION

       The "ptal-init" script may be called on the command line or by your
       system’s startup and shutdown sequences to automatically start and stop
       the hpoj daemons ("ptal-mlcd", "ptal-printd", and "ptal-photod").  It
       also serves as a convenient tool for managing (adding and removing)
       devices of all connection types (parallel, USB, or JetDirect) which
       should be controlled by the hpoj daemons.  Click here for more
       information on setting up basic device connectivity with the hpoj
       software.

OPTIONS

       ·   "command" is one of:

           ·   "start", "restart", or "reload" to both stop and (re)start the
               daemons

           ·   "stop" to stop the daemons

           ·   "setup" or "probe" to add or remove devices

           ·   "status" to return 0 if started or 1 if not (any user may call
               this)

           ·   "condrestart" to restart only if already started

       ·   "-verbose" -- also lists daemon start command lines for debugging

       ·   "-quiet" -- suppresses the "stopping" and "starting" messages

NOTES

       "ptal-init" contains a special comment line telling the RedHat
       "chkconfig" to start "ptal-init" in runlevels 2, 3, 4, and 5, and stop
       it in other runlevels, with a start order of 59 and a kill order of 61.
       These settings are based on the following dependencies and assumptions:

       ·   "lpd"’s start and kill orders are both 60, because "ptal-printd"
           needs to be started before "lpd".

       ·   CUPS’s start order is 90 and kill order is 10, because "ptal-mlcd"
           needs to be started before CUPS.

       The version of Perl shipped with RedHat 9 has a bug with regular-
       expression parsing (such as when "ptal-init" reads its configuration
       files) when used in a UTF8 locale (as defined by the "LANG" environment
       variable).  "ptal-init" works around this problem by re-invoking itself
       with a non-UTF8 locale if necessary.  If something goes wrong with this
       workaround, an alternative way to fix this is to edit the file
       "/etc/sysconfig/i18n" and change the "LANG" setting to "C".  When
       installing hpoj on other distributions that lack "chkconfig", start
       "lpd" or CUPS in a different order, or don’t even have a SysV-style
       init subsystem, then you may need to manually integrate "ptal-init"
       into your system’s startup and shutdown sequences.  ""ptal-init setup""
       has a list of known possible wildcard patterns to match parallel and
       USB printer device nodes on various platforms.  If necessary you may
       update this list by editing the definition of @parWildcards and/or
       @usbWildcards near the top of the "ptal-init" script.  "ptal-init" is
       derived from "ptal-init.in" by the "./configure" script, after
       substituting in the $prefix (installation base path) variable.
       "ptal-init" erases and re-creates the socket/pipe directories needed by
       "ptal-mlcd" and "ptal-printd".  Previous hpoj versions expected these
       directories in "/dev", but they are now located in "/var/run", because
       some platforms have a read-only "/dev" file system.  For backwards
       compatibility it attempts to create a symlink from "/dev/ptal-printd"
       to "/var/run/ptal-printd" so you don’t necessarily need to re-create
       print queues when upgrading from an earlier hpoj version.  If either
       the directory "/var/lock/subsys" or "/var/lock" exists, "ptal-init"
       creates and deletes the file "ptal-init" in that directory.  This is
       needed for the SysV init system in RedHat and possibly other
       distributions.  For Linux, "ptal-init" attempts to run the commands
       ""/sbin/modprobe lp"" and ""/sbin/modprobe printer"" before probing for
       and starting daemons for the first parallel- and USB-connected device,
       respectively.  (Exception: this is not done for USB-connected devices
       if "ptal-mlcd" was compiled for "libusb" support and it’s running on
       SMP (multi-processor) Linux.)  Previous versions didn’t do this for
       ""ptal-init start"", which sometimes resulted in a situation where
       ""ptal-init setup"" configured the device successfully but device
       connectivity was lost after a reboot.  ""ptal-init start"" delays two
       seconds before starting the first instance of "ptal-photod", to
       increase the chance that the kernel has had enough time to release the
       TCP port used by the previous instance of "ptal-photod" so that the
       same TCP port number (and therefore "mtools" drive letter) will be used
       for the new instance.  Notes on the "setup" command ""ptal-init setup""
       walks you through the following steps, prompting you for confirmation
       or other information when necessary:

       ·   Deleting devices if desired

       ·   Probing for parallel-connected devices (Linux and FreeBSD only)

           ·   For Linux kernels 2.2.x, 2.4.x, and possibly later versions,
               parallel ports are auto-detected based on information found in
               the "/proc" file system.

           ·   You may manually enter base address and kernel device node
               information for parallel ports which were not auto-detected.

           ·   Because probing a specific parallel port can be dangerous if
               incorrect base address information is supplied, you must
               confirm (default=no) the relevant port information before the
               probe will take place.

       ·   Probing for USB-connected devices (only Linux and (theoretically)
           other "libusb"-supported platforms)

           ·   "libusb" device names are of the form ""%bus%device"".

       ·   Setting up JetDirect-connected devices

           ·   Currently the network is not automatically probed for
               JetDirect-connected devices.  Instead, you must enter the
               hostname or IP address and port number (for multi-port
               JetDirects such as the 500X).

       ·   Setting or un-setting the default device name (only if multiple
           devices and/or a default device name have already been configured)

       ·   Starting the daemons for currently registered devices

       The following ""ptal-init setup"" yes/no prompts allow you to
       optionally append (after an explicit "[y]es" response) additional
       command-line switches that should be passed to "ptal-mlcd" probe
       instances and to any new devices that are added as a result:

       ·   whether to probe for parallel-connected devices in general

       ·   whether to probe for a device on a specific parallel port

       ·   whether to probe for USB-connected devices in general

       For the sake of succinctness this capability is not mentioned in the
       on-screen messages.  For example, if you want to turn on more warning-
       message output while "ptal-mlcd" probes devices, you can answer the
       appropriate yes/no questions above as ""y -logwarn"" (be sure to put a
       space between the explicit "[y]es" response and the appended command-
       line option(s)).  Or, a if composite USB device is giving you trouble
       and you want to disable this capability and revert to a pure MLC/1284.4
       communication model, then you can enter ""y -nocomp"".  The Linux
       kernel USB printer-class driver ("printer.o") currently has stability
       issues on SMP (multi-processor) systems, at least through the 2.4
       kernel series.  ""ptal-init setup"" now checks whether your system is
       running in SMP mode before probing for USB devices and (if necessary)
       offers to update "/etc/modules.conf" and "/etc/hotplug/blacklist" to
       prevent "printer.o" from being auto-loaded in the future.  This allows
       the more robust "libusb" communication method to be used instead.  Note
       that this will prevent all use of USB printers via direct access of
       "/dev/usb/lpX" device nodes, which would be an issue in conjunction
       with non-hpoj-supported single-function or non-HP printers.  If you
       ever want to undo these changes to allow "printer.o" to be loaded in
       the future, then be sure to update both files ("/etc/modules.conf" and
       "/etc/hotplug/blacklist").  Similarly, the Linux kernel USB "scanner.o"
       driver has a bug where it inappropriately tries to bind to certain hpoj
       devices (PSC 1210 in 2.4.22 and 2.5/2.6.0-test; also PSC 750 but in
       practice this model isn’t actually affected).  Therefore, ""ptal-init
       setup"" tries to detect this situation by parsing the file
       "/proc/bus/usb/devices" and offering to disable and unload "scanner.o"
       the same way it does as described above with "printer.o" on SMP
       systems.  Note that this may break any USB single-function scanners you
       might also have connected, and you will need to either reconfigure the
       affected devices to use "libusb" if possible, or
       modify/recompile/reinstall "scanner.o" to not bind to your hpoj device.
       Both of the above "detect+blacklist+unload" workarounds for "printer.o"
       and "scanner.o" issues will probably not work correctly if the relevant
       kernel modules are renamed (or in the case of "scanner.o", compiled
       into the kernel instead of dynamically loaded as a module).  When
       probing a device, ""ptal-init setup"" performs the following actions:

       ·   Before probing the first USB device, starts a "glob" instance of
           "ptal-mlcd" to return (via the special "PTAL-MLCD-GLOB-DEVNODES"
           service) a list of possible USB kernel and "libusb" device nodes.

       ·   Starts a "probe" instance of "ptal-mlcd", except for JetDirect-
           connected devices.

       ·   Queries the model and serial number strings and ensures that at
           least a non-blank model name was returned, meaning that "ptal-mlcd"
           was successful in establishing bidirectional communication with the
           device.

           ·   Else if the model name couldn’t be read, attempts to read the
               "previous" device ID string to determine if "ptal-mlcd" could
               read the device ID string but not establish bidirectional
               communication.

       ·   Uses the model name, serial number, and parallel-port base address
           (if applicable) to determine if this device has already been set
           up, except for JetDirect-connected devices.

       ·   Proposes a default device name and prompts you to confirm or change
           it or skip setting up this device, except for JetDirect-connected
           devices.

       ·   Deletes old devices which conflict with this new device in name or
           parallel-port base address (if applicable), for example if you
           moved a device around from one parallel port to another or replaced
           a device with another of the same model with a different serial
           number.

       ·   Creates the new device’s configuration file:

           ·   Writes the file version.

           ·   Writes the model and serial-number strings (if any).

           ·   Enables "ptal-mlcd" and "ptal-printd", except for JetDirect-
               connected devices.

           ·   Probes the device for photo card-reader support and enables
               "ptal-photod" if appropriate.

       ·   Reads the new configuration file back in so the necessary daemons
           can be started later.

       In most cases, "ptal-mlcd" now properly handles situations where you
       have more than one instance of the same model connected locally, with
       the following caveats:

       ·   For parallel connections, different parallel ports (with different
           base addresses) are sufficient to uniquely identify each device.

       ·   For USB connections, each device must include a unique serial
           number field in the device ID string, not just in the USB
           descriptors.

       ·   You still need to specify unique device names in the above cases,
           unless you want to replace one device with the other.

       ·   As a consequence of this more robust unique-device detection, if
           you move devices between parallel ports or replace a device with
           the same model but a different serial number, then you must re-run
           ""ptal-init setup"" to delete and re-probe the affected device
           names.  Alternatively, if you want to relax the unique-device
           detection, you can comment out the lines in the device’s
           configuration file that specify the model and/or serial number
           strings.

       ·   If you connect via USB two identical models with no unique serial
           number in the device ID string (for example, two LaserJet 1220s or
           3200s), then ""ptal-init setup"" will only create one device name,
           with the effect of setting up a form of "fail-over" redundancy in
           case one gets powered off or disconnected, but not necessarily
           properly handling all possible failures.  If you want to be able to
           address each device separately, then "cd" into the "/etc/ptal"
           directory and copy the applicable device configuration file to a
           new name, keeping the "mlc:usb:" prefix, and run ""ptal-init
           start"".  Even so, it is still rather unpredictable which device
           name maps to which device.

       ·   For JetDirect connections, the hostname or IP address and port
           number determine the device name.  However, currently "ptal-init"
           incorrectly adds duplicate device name entries if you’re
           inconsistent about using either the IP address or the same hostname
           all the time.  If you accidentally add duplicate devices, then use
           ""ptal-init setup"" to prune the device list as necessary.

       Device configuration file format hpoj device configuration files, which
       "ptal-init" manages, are stored in the directory "/etc/ptal".  For each
       configured device, there is a file in this directory whose name is the
       PTAL device name, such as "mlc:par:OfficeJet_Series_700",
       "mlc:usb:PSC_750", or "hpjd:my-jdex.my-domain.com:3".  "libptal"
       applications such as "ptal-devid" or "libsane-hpoj" use the presence
       and names of these files to determine the list of configured devices.
       "ptal-init" uses the contents of each file to determine what daemons,
       if any, it should start for the corresponding device and what command-
       line parameters to pass.  The following rules govern the format of
       device configuration files:

       ·   Comment lines start with a "#" character.

       ·   The line ""key=value"" assigns "value" to "key", replacing any
           previous value of "key".

       ·   The line ""key+=value"" appends "value" to any existing value of
           key.  A space character is also added between the old and new
           values if necessary.

       ·   End-of-line comments and backslash-style line continuation are not
           currently supported.

       ·   The following keys are currently recognized:

           ·   "init.version" -- The file format version.  If this key is
               missing or has a different value from that which "ptal-init"
               expects, then "ptal-init" ignores the device, and you must run
               ""ptal-init setup"" to delete and re-probe the device.

           ·   "init.mlcd.append" -- Additional command-line parameters to
               pass to "ptal-mlcd".

           ·   "init.printd.start" -- Non-zero to start "ptal-printd" (default
               for parallel- and USB-connected devices), zero to not start
               "ptal-printd" (default for JetDirect-connected devices).

           ·   "init.printd.append" -- Additional command-line parameters to
               pass to "ptal-printd".

           ·   "init.photod.start" -- Non-zero to start "ptal-photod" (default
               is zero, which means not to start; ""ptal-init setup"" sets
               this to non-zero if it detects photo-card support on the
               device).

           ·   "init.photod.append" -- Additional command-line parameters to
               pass to "ptal-photod".

       ·   If you have multiple devices and want to set identical keys for all
           devices, such as ""init.mlcd.append+=-remconsole"",
           ""init.printd.start=0"", or ""init.printd.start=1"", then you may
           add them to the file "/etc/ptal/defaults", which has the same
           format rules above, but any commands are read and processed before
           the commands in each specific device configuration file.

       In addition, the default device name (if set) is stored in the file
       "/etc/ptal/default-device", and the file "/etc/ptal/ptal-printd-like"
       stores permissions copied from a previously-seen printer-device node
       and is passed as a template to ""ptal-printd -like"".  The
       "ptal-start.conf" and "ptal-stop.conf" files used in hpoj-0.8 are now
       obsolete.