NAME

info - remote device capability database  

DESCRIPTION

The info subdirectory in the HylaFAX spooling area holds information about the capabilities and status of devices that have been called. One file exists for each device, with the filename created from the remote device's fully-qualified phone number. Files have a simple ASCII format. Each line is of the form


      [&]tag: value

where a tag identifies a capability and a value is either a string, number, or boolean value. An optional ``&'' at the front of the line indicates that the tag's value is locked down and should not be updated by the server. This facility is useful for restricting the capabilities used with a particular machine.

The following items are recorded: 

Tag                   Type       Description
calledBefore          boolean    device has previously answered at this number
dialFailures          number     count of consecutive failed dial operations
hasV34Trouble         boolean    there is difficulty sending to this destination with V.34
hasV17Trouble         boolean    there is difficulty sending to this destination with V.17
lastDialFailure       string     reason for last failed dial operation
lastSendFailure       string     reason for last failed send attempt
maxPageWidth          number     maximum page width in pixels in normal resolution
maxPageLength         number     maximum page length in millimeters
maxSignallingRate     string     maximum signalling rate (bits/sec) to use
minScanlineTime       string     minimum scanline time
pagerMaxMsgLength     number     length of longest allowed text message
pagerPassword         string     password string send to service provider
pagerSetupCmds        string     commands for setting up modem for a specific service provider
pagerTTYParity        string     parity & # bits configuration for IXO/TAP communication
pageSource            string     parameter to tell the paging central who we are
pagingProtocol        string     protocol (IXO or UCP) for this provider
remoteCSI             string     remote device Called Subscriber Identification
remoteNSF             string     remote equipment Non-Standard Facilities information
remoteDIS             string     remote Digital Identification Signal: capabilities
sendFailures          number     count of consecutive failed send attempts
dataSent              number     units of data sent to the destination in the last session
dataSent1             number     units of data sent to the destination in the session previous to the last
dataSent2             number     units of data sent to the destination in the session previous, previous to the last
dataMissed            number     units of data sent to the destination which were missed or corrupt in the last session
dataMissed1           number     units of data sent to the destination which were missed or corrupt in session previous to the last
dataMissed2           number     units of data sent to the destination which were missed or corrupt in session previous, previous to the last
senderDataSent        number     units of data sent by the sender in the last session
senderDataSent1       number     units of data sent by the sender in the session previous to the last
senderDataSent2       number     units of data sent by the sender in the session previous, previous to the last
senderDataMissed      number     units of data sent by the sender which were missed or corrupt in the last session
senderDataMissed1     number     units of data sent by the sender which were missed or corrupt in session previous to the last
senderDataMissed2     number     units of data sent by the sender which were missed or corrupt in session previous, previous to the last
senderHasV17Trouble   boolean    there is difficulty receiving from this caller with V.17
senderSkipsV29        boolean    this caller does not use V.29 in the presence of V.17
supportsBatching      boolean    accepts batching protocol
supportsHighRes       boolean    accepts 196 line/inch images (obsolete)
supportsVRes          number     vertical resolution support bitmask
supports2DEncoding    boolean    accepts Group 3 2D encoding
supportsMMR           boolean    accepts Group 4 encoding
supportsPostScript    boolean    accepts Adobe POSTSCRIPT transfer protocol

The HylaFAX scheduler, faxq(8C), uses the information stored in this directory when deciding if a call should be placed and when preparing documents for transmission. If a remote device's capabilities are known, then document preparation is constrained and/or optimized according to the capabilities. Otherwise, documents are prepared without regard for the remote device's capabilities and if a capability mismatch is encountered the session is terminated and the documents are reformatted using the newly discovered capabilities.

The calledBefore item is used by faxsend to decide whether or not to redial a phone number when encountering certain errors. For example, if a dialing command results in a ``NO CARRIER'' result, then the number will not be retried unless the number has previously been dialed successfully.

The minScanlineTime item indicates the minimum scanline time parameter used for facsimile transmissions. Acceptable values are: ``0ms'', ``5ms'', ``10ms/5ms'', ``10ms'', ``20ms/10ms'', ``20ms'', ``40ms/20ms'', and ``40ms''. (Values of the form X/Y mean to use X for 98 lpi images and Y for 196 lpi images.)

The pagerTTYParity item specifies the communication parameters to use when communicating with the IXO/TAP service provider. Acceptable values are: ``even'' (7 bits, even parity), ``odd'' (7 bits, odd parity), and ``none'' (8 bits, no parity). If nothing is specified then ``even'' is used per the standard.

The pagerMaxMsgLength, pagerPassword, and pagerTTYParity items can be setup according to the requirements of a pager service provider; they typically are locked down so that their values are not lost during updates.

The pagerSetupCmds can be used to define AT commands for setting up the modem for a specific service provider. This value overwrites the settings defined in hylafax-config(5F).

The pageSource parameter can be used to tell the paging central who we are. It usually contains a SMS answerable mobile number. It is only used for the UCP part of sendpage(8C). Note: This parameter should be used from user-land sendpage(1) and will be removed later.

The pagingProtocol defines which protocol, UCP or IXO, should be used to send the message to the service provider. It defaults to ``ixo''; for UCP set ``ucp''.  

NOTES

faxsend, pagesend, and faxq automatically create and update entries in the info directory, as required.

The data in this directory is simply a cache of remote capabilities and, except for locked down items, can be safely purged at any time. The faxcron(8C) script, for example, periodically purges unlocked entries in this directory that have not been accessed in 30 days.

When the first batching attempt fails then supportsBatching is set to false. It must be manually altered in order to re-enable batching to the destination.

Restricting the capabilities used with a particular machine to a value other than those that are mandatory can cause documents to be sent outside of an acceptable range for the receiver.  

SEE ALSO

faxcron(8C), faxq(8C), faxsend(8C), pagesend(8C), hylafax-config(5F)