info - remote device capability database
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
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
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(8), 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
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
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(5).
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(8). 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''.
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(8) 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
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.
faxcron(8), faxq(8), faxsend(8), pagesend(8), hylafax-config(5)
February 10, 1996