The following tools are not production-ready. They are included only as
conveniences, examples or rudimetary starting points for other development
efforts.

skyview2svg reads the skyview from gpspipe, and creates an svg image
of the skyview.

gpssnmp a tool to return some SNMP values from the running local gpsd.
 
clock_test is used to test the latency of the system call clock_getttime().

binlog and binreplay are probably only useful for people developing
drivers for new protocols, when gpsfake does not yet know what to do
with a log file. These utilities are not particularly clever - they
merely slurp a tty's output into a file, or spray the contents of a
file out of a tty.

ashctl might be used to reset an uncooperative Ashtech receiver to
a usable state. For whatever reason sometimes they do not respond to
a protocol switch command; this spams the receiver with configuration
commands, and hopefully it listens.

motosend is like ashctl, but for receivers that use the motorola
protocol (like motorola oncore or rockwell jupiter). it's a little
buggy with syncing up to the start of a packet, but it'll send control
strings OK.

lla2ecef transforms latitude/longitude/altitude (aka north-east-up or local
tangential plane) coordinates into the earth-centered-earth-fixed frame. If
invoked as "ecef2lla" it will transform coordinates in the opposite manner.

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The files below have been tested to work with gpsd v3.14, as of 2015-03-23

webgps.py draws a sky view of the satellites and their tracks using HTML5. It
needs to run continuously in order to build a history and generate the
satellite tracks. Your browser must be able to display the <canvas> element to
display the satellite view properly. webgps.py can be called with the argument
"c" to run continously, with an integer duration and a unit suffix to run this
long (units allowed are "s", "m", "h" and "d", e.g. "4h"), or without argument
to create a snapshot of the current sat view.

ntpoffset generate an estimate of your GPS's offset from a peerstats
file.  For instructions on how to use this script, see the GPSD Time
Service HOWTO in this distrubution, in the www/ subdirectory.

skyview.php is used to generate pictures of your skyview, and may be
used to help determine if a given antenna placement is appropriate for
some purpose. This tool take a count of samples to collect from GPSD, and
outputs an image of accumulated SV position and signal strength. It is
sometimes entertaining to "see" occulted SVs using multipath. You must
have the PHP-GD library installed to use this script.

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The files below do not work with current versions of gpsd.

[The GPSD protocol changed in 2.90, and messages emitted are no longer
of the form that this script expects.]

maxsats.pl analyzes a collection of "Y" messages and outputs records
describing periods of excellent visibility (ie. 10 or more PRNs tracked).
With over 30 SVs on orbit, there are periods where 14 PRNs are above the
horizon, 13 are tracking, and at least 12 are actually used in a solution.