Enhancement: added gps_antenna_height command to simplify testing antenna height errors in GNSS observations.
Enhancement: added wildcard handling for datafile based modifications in the reject, reweight, and ignore observations commands. Previously this was not handled consistently with other criteria.
Bug fix: fixed a bug which could cause concord to hang with concords more than 180 degrees from expected range.
Breaking change: The handling of vertical datums and geoid information in coordinate files has been rationalised. The two changes are:
These changes are considered worthwhile, despite potentially breaking existing adjustments, as they are simpler, and more intuitive.
Bug fix: In a CSV file format definition, if the required columns command is not specified then every column that is referenced in the . is considered required, unless there is also a default for the value it defines. Also added an optional_columns command in a format definition file that allows explicitly specifying that columns are optional.
Enhancement: Fixing handling of degrees/minutes/seconds input and output when a field separator is specified
Enhancement: Limited support for spaces in file name. Currently does not include format files (.dtf) and not supported in snap_manager. Also filenames with spaces will not work in datafile based classifications, for example in observation modification.
Enhancement: Search path used for configuration files used in snap commands (such as CSV format definition files) now includes directories of all snap command files used to define the command. That is, if the command is in a command file which in turn is included from a "parent" file, then snap will first search the directory of the command file in which the configuration file is referenced, then in the parent directory, and so on.
Fix: The highlighting of the current station or observation has been fixed in ubuntu.
Breaking change: the windows help system used for SNAP (windows help compiler) is no longer supported my Microsoft. The help system has been replaced with a set of HTML pages displayed in the user's browser.
Breaking change: Reading of CSV format definition (.dtf) files has slightly changed. SNAP will now issue warnings on some .dtf files where column values or strings are not explicitly defined. The filed installed with SNAP have been updated to reflect this. The contractor snap package has also been updated with new .dtf files.
Enhancement to support use of degrees/minutes/seconds angle formats in input CSV data and station files.
Added GDA2020 coordinate system and related MGA projections.
Enhancement to allow use of wildcards in classifications on observation modification commands. See for example the reject_observations command.
Added flushing of the SNAP output files periodically to help monitoring long running jobs.
Fixed import of coordinates to use the updated URL for the LINZ geodetic database
Enhancement: experimental feature for adding offset and centroid errors to GNSS data type covariances. See the reweight_observations command
Bug fix: Fix snapplot crashing
Bug fix: Corrected handling of constrained stations
Enhancement: Improved memory allocation for very large adjustments (avoiding allocation of huge memory block)
Enhancement: Added configuration options for output files, horizontal/vertical configuration, including untested orders (no_test)
Enhancement: Added set_observation_option command and option for calculating GX data set translation
Enhancement: Improved handling of wildcards in parameter commands
Bug fix: Fixed float command when applied to fixed station
Enhancement: snapspec performance enhancements for large adjustments working on decomposition rather than full normal equations inverse (only requires inverting equations once).
Enhancement: improved output and debug information
Enhancement: More performance improvements loading very large data sets.
Bug fix: Minor fixes to JSON debugging output.
Enhancement: Fixes to output CSV file and improved logging information
Bug fix: Fixed errfct values for vector data in -obs.csv file.
Enhancement: Performance improvements loading large data sets with many observation modifications.
Bug fix: Fixed errors in order calculation when using two pass calculation.
Bug fix: Fixed source order values in output csv file.
Enhancement: Refactoring two pass calculation to only calculate inverse once. See snapspec for details.
Enhancement: Adding option to cache inverse results for multiple snapspec runs.
Enhancement: Adding CSV format output file for easier process integration.
Enhancement: Tidying command line options.
Bug fix: Fixing dat2site bug creating output file with -f option.
Enhancement: Added output_csv filelist option to create catalogue of files used in snap adjustment
Enhancement: Improved handling of wildcards in snap station lists
Enhancement: Enhanced add_coordinate_file command to allow adding coordinate files which need an epoch for coordinate conversion
Enhancement: Added feature to ignore_missing_stations to allow ignoring explicit stations to provide more targeted error reporting
Enhancement: Added station priority option to snapspec to provide better control over which stations get higher orders
Enhancement: Added support for recoding with co-location error - recoded location differs from original location by defined horizontal and vertical error.
Enhancement: Tidied output of dates removing 00:00:00 from most output where the date doesn't include a time
Enhancement: Added special refraction coefficient "zero"
Enhancement: Improved test suite to facilitate running all tests for release
Bug fix: Fixed bug recoding snap format point data with more than one observation per line of data
Enhancement: Updating wxwidgets library to version 3
Enhancement: Added use_zero_inverse command to allow generating limited statistics without performing complete inversion of normal equations
Enhancement: Added support for using multiple coordinate files
Enhancement: Added support for using multiple coordinate files
Enhancement: Added trial version of multithreaded normal equation inversion
Modified EGM96 definition to be based on WGS84_G1762 rather than WGS84_D (for practicality)
NZGD2000 coordinate system updated to version 20171201 including Kaikoura earthquake update.
Enhancement: Added the by_set option to the reweight_observations command.
Enhancement: Added option list xyz_vector_residuals to display vector residuals in XYZ oriented components rather than default ENU components
Enhancement: Coordinate system codes can include an alternative reference frame code in brackets, for example EDENTM2000(NZGD2000_20140201).
Enhancement: coordsys.def datums and coordinate systems can include aliases for codes, eg NZGD2000=NZGD2000_20160701.
Enhancement: Listing file now includes the runtime user name.
Bug fix: Dates read in year/day number format were out by one day.
Bug fix: Fixes error between converting coordinate systems with height reference surfaces
Bug fix: Some of the probability distribution functions were giving incorrect results for high degrees of freedom (eg chi-squared distribution for dof > approx 1800). Thanks to Denny Fiedler for identifying this issue.
Bug fix: Fixed the handling of numerical codes in station lists so that, for example, R10-R100 includes R20, rather than being treated as purely alphabetic.
Enhancement: The coordsys.def file can now include definitions of vertical datums (in principle geoids, but can also include the 2016 local vertical datums. These can be used to define geoid undulations and deflections of the vertical rather than using a geoid file. This also means that concord can be used to convert between different vertical datums (eg between NZVD2009 and NZVD2016, or between NZVD2016 and the local vertical datums based on it). This affects in particular concord, snapconv, snapgeoid, as well as snap itself.
Enhancement: New commands reweight_observations, reject_observations, and ignore_observations replacing the classification command. These improve the readability of the command file and provide additional functionality for selecting observations based on multiple criteria including observation date and stations used.
Enhancement: Station lists are more sophisticated and can select stations based on multiple criteria, for example selecting order 0 or 1 stations outsidels a geographical area.
Enhancement: Added functionality to automatically fix or float stations horizontally or vertically. See the fix frame command documentation. Also the algorithm used to automatically reject stations is more rigorous than it used to be (based on types of observations at each station, not just on the number of observations). This may result in more stations being automatically rejected than was previously the case.
Enhancement: The geoid command can accept stations outside the extent of the geoid file. The geoid information from these stations is unchanged.
Enhancement: SNAP is now able to read SINEX data with either upper or lower triangular format covariance data.
Enhancement: Tidied up handling of included snap files to better handle including files in subdirectories.
Bug fix: Corrected handling of geoid function when input coordinate file defines ellipsoidal heights.
Enhancement: Added support for vertical datums and converting coordinates between them (eg between local vertical datums and geoid datums).
Bug fix: corrected the order 2 vertical specification in the configuration file
Enhancement: Better error handling options in station lists - options for handling ignoring stations not in coordinate file
Enhancement: Better error handling in classification command
Enhancement: Making some error messages more specific and useful
Enhancement: modified geoid handling to simplify adding new geoid models.
Enhancement: Adding version 20160701 of New Zealand Deformation Model and NZGeoid2016
Enhancement: Including old versions of deformation model to allow conversions between versions (with care!)
Bug fix: Modifying geoid calculations to use bilinear rather than bicubic interpolation. This makes the calculation consistent with the LINZ standard for geoid calculation.
Bug fix: summarise_residuals_by option did not work correctly if not summarizing by data_type
Bug fix: SNAP command files could be corrupted by UTF8 byte order marker (BOM). Updated to ignore byte order marker.
Bug fix: Fix for reading CSV files with more than one data type per line and first item blank.
Enhancement: Improved handling of XYZ format in CSV coordinate file.
Bug fix: Fixed error reading SINEX files whereby sign of X,Y,Z coordinate values can be lost.
Bug fix: Fixed error in sign of 14 parameter transformations. Clarified definition of transformations in help file.
Enhancement: Station codes can now be up to 15 characters long (previously this was limited to 10 characters)
Enhancement: Station lists can specify ranges such as 2-10 for which the start and end values do not need to be existing codes. Previously ranges were only valid if both endpoints were listed station.
Enhancement: Station lists can specify stations using a "*" wildcard as the last character. For example BO* will match any station code starting BO.
Bug fix: Fixed bug whereby the covariance matrix of grouped vector data was corrupted if one or more stations in the set are ignored.
Bug fix: Fixed bug whereby SNAP would still run despite errors in a command file.
Enhancement: Reference frames for GNSS baseline and point position data can now include time dependent terms (rates of change of translation, scale, and orientation). Note: this has required some changes to the reference frame command which means that some old command files may need modification to work as previously. Also added to the reference frame options in the list command.
Enhancement: SNAP can read observations from SINEX files
Enhancement: SNAP has two new output formats - SINEX and JSON. The JSON format can be directly read by scripting languages such as perl and python. See details for the output command.
Enhancement: Added the recode and data_file .. recode commands to allow recoding stations read from command file. This allows stations in data files to be recoded, optionally for specific date ranges. This can be used where stations are miscoded in data files, to test if stations have moved for specific ranges of dates, and to remove observations from data files (in the same way as the ignore command).
Enhancement: Added station offset file command in snap configuration, allowing a time history of coordinate offsets to apply at each station.
Enhancement: Added an option for selecting station inside or outside a polygon area in station lists.
Enhancement: Added min_iterations command.
Enhancement: Fixed precision of GX (GPS point position) data in output.
Enhancement: Increased precision of GPS datum transformation parameters.
Enhancement: Changed format of dumped observation equations to JSON format to more easily import into other software.
Enhancement: Conversion of coordinate systems requiring conversion date.
Enhancement: Modified coordinate file conversion dialog to include conversion date.
Enhancement: Improved configuration file dialog with import/export/delete.
Enhancement: Coordinate output respects coordinate precision specified in snap command file.
Bug fix: Fixed default coordinate accuracy used for decimal lat/lon coordinates.
Enhancement: The command line options have been "conventionalised" to allow space be between the option and value.
Enhancement: dat2site (calc missing stations option in snap_manager) now handles CSV formatted data when reading station and data files from a snap command file.
Enhancement: Updated to version 20150101 of NZGD2000 deformation model. Extends coverage of deformation model to include the extents of the NZ Exclusive Economic Zone.
Enhancement: Using a new version of the LINZ deformation model binary format that better suits the definition of the model using nested grids rather than additive subgrids. This means that only one grid needs to be evaluated at each location.
Bug fix: Fixed mismatch of column names and values in some output csv files
Enhancement: Added height_difference_error option to CSV observation file format definition.
Enhancement: error_type option allows specifying confidence limits for error ellipses.
Enhancement: Added option to display system configuration data from Config menu.
Bug fix: Fixed bug generating log file name which could cause a program crash.
Bug fix: Some bug fixes where a non-blank separator is used, handling properly blanks at at the end of data fields and copying non coordinate lines with the -E option.
Update: the NZGD2000 deformation model has been updated to version 20140201 incorporating the 2013 Cook Strait and Lake Grassmere earthquakes as forward patches
Enhancement: Added configuration menu for managing the various types of configuration files
Enhancement: Updates to snap_manager scripting language. The main feature is allowing a function to return multiple values. Also additional function (MakeDir) and dialog option (new_row). Bug fix on missing return value when return is in a foreach loop.
There are two main changes in this release of SNAP
Enhancement: Added option calculating errors of angle errors in observations files based on angle error and constant error. (But note that this is based on the calculated length based on the input coordinates - it is not updated as the coordinates change at each iteration
Bug fix: Obscure bug in calculating errors of residuals of grouped GPS vector observations when some of the vectors in the group are rejected.
Bug fix: Sorting list of observations was not working properly if the observations did not have an observation id
Enhancement: Observations dates are more displayed in the observation lists, and dates include times.
Modified GDB import to clear existing coordinate orders before importing from GDB by default
Added options to clear coordinate orders for coordinate files being merged.
Altered behaviour to not reject stations if no relative accuracy tests are defined.
Enhancement: concord supports time dependent Bursa-Wolf transformations, and also for printing additional textual information associated with coordinate systems and transformations.
Note: SNAP binary files have changed in this release - binary files from old adjustments cannot be loaded and will need to be rebuilt.
Enhancement: SNAP can read station coordinates and observations from CSV files (character delimited text files) as well as SNAP formatted text files. The encoding of information in the text files is controlled by CSV format definition configuration files.
Enhancement: SNAP can output CSV (comma separated value) formatted files of adjustment results (station/coordinate information, observation information, and adjustment metdata). This simplifies importing adjustment data into other analysis packages. CSV format files are generated using the output_csv command in the SNAP command file. Note that this feature is "under development" - the implementation is likely to change in the next release of SNAP.
Enhancement: SNAP is able to calculate the geoid undulation and deflections of the vertical from the geoid model after loading the coordinates, so that this can built into the adjustment configuration, rather than relying on the user to run the sngeoid program. This is done with the geoid command in the SNAP command/configuration file.
Enhancement: The coordsys.def file can include a specification for a deformation model associated with the datum. SNAP will use this model by default, unless it is overridden by a deformation command in the SNAP command file. Note that the deformation model currently included in coordsys.def is still the IGNS98 model. This is under development and may change with the next release.
Enhancement: The handling of bearing orientation errors, distance scale errors, refraction coefficients, and vector reference frames has been modified. Each of these previously had values defined by codes used in the data file using #bearing_orientation_error, #distance_scale_error, #refraction_coefficient, and #reference_frame data definition commands in the configuration files. Now they can be defined defined in terms of any observation classifications in the data as selected by parameter commands in the command file. This makes it easy to test the effect of different factors on these parameters.
Enhancement: SNAP observations can include an integer observation id. This is not used at all by SNAP, but is displayed in outputs. This is mainly for data from other sources, and allows for easy matching of the output information with the source data. The id is defined using either the #data command in SNAP format observation files, or in the CSV format definition file for CSV formatted observations.
This program has been renamed to snaplist
Change: updated import GDB stations function to use revised web location.
Bug fix: Error in calculation of LINZ deformation model (this does not apply to the simple grid deformation model used in NZGD2000 prior to this date).
Bug fix: Some observations were not displayed in the observation list
Bug fix: Line lengths were not displayed in observation list
Enhancement: Added support for importing Antarctic stations
Enhancement: Added the site2gps program back into the SNAP suite for distribution.
Bug fix: Using options like order=1 in station list would pick all marks with no order defined if there were no stations of order 1.
Change: Changed configuration files for specification testing in snap and snapspec to reflect changes to LINZ accuracy standards.
Change: Removed the relationship between Camp Area datum and WGS84. This was incorrectly assumed to be the same as the WGS72 relationship (based on Doppler observations). In fact the datum predates the Doppler observations and the relationship is undefined.
Enhancement: Added XYZ position, mean sea level distance, orthometric height and ellipsoidal height data types.
Enhancement: Added options for all angles and angle errors to be entered in degrees instead of degrees, minutes, seconds.
Change: The binary format used for triangulation data has been changed. This only affects deformation models with triangulated patches. Currently no such models have been published, but possible future models will use this format.
Change: Updated accuracy specifications of NZGD2000 orders in configuration files reflecting new Surveyor General standards.
Change: Updated accuracy specifications of NZGD2000 orders in configuration files reflecting new Surveyor General standards.
Bug fix: Fix to bug causing SNAP to require observation dates in data files even when the adjustment does not include a deformation model.
The NZGeoid09 geoid model replaces the previously used unofficial NZGeoid05. This affects concord and snapgeoid.
The scale factor of the WGS72 coordinate system has been changed to match that in PROJ and EPSG. This will affect calculated heights only.
Enhancement: Added ability to use a full LINZ deformation model, including ongoing national deformation components and local "patches".
Enhancement: Added "output decomposition" option to include the Choleski decomposition of the normal equations in the binary file (for use by snapspec instead of using the using the full covariance matrix).
Enhancement: Coordinate files can now include additional columns of station classifications. These can be used in SNAP to select groups of stations for processing (for example in the "fix" command). They can also be used in snapplot for colour coding stations.
Enhancement: added facility to allow colouring stations by classification (such as order, etc) as well as the default colouring by usage.
Enhancement: Modified to allow use of the Choleski decomposition instead of the full coordinate covariance matrix. Also added a number of optimisations for calculating orders.
Enhancement: Added testing of vertical as well as horizontal accuracy specifications.
Enhancement: Added "limit_order" and "configuration" commands to snapspec configuration to allow constrain the orders that stations can be assigned to (for example according to mark type) and to allow configuration to be defined in multiple files.
Enhancement: Update antarctic coordinate systems (Darwin Glacier Lambert Conic).
Bug fix: Corrected calculation of orders when using a posteriori statistics.
Change: Updated the import GDB stations function to reflect changes to the LINZ website.
Change: Tidied up Chatham Islands coordinate systems in coordsys.def. Replaced CHATTM1979 with CITM1979. Removed CHAT (which is the same as CHAT1979).
Enhancement: Added listgps software to SNAP distribution
Enhancement: Removed limit of 32,000 stations imposed by use of 16bit integers. Note that binary files from previous versions are incompatible with this version. Updated version of all SNAP utilities to 2.3.0
Maintenance: Updated wxWidgets graphics library used by snapplot and snap_manager to version 2.8.7.
Enhancement: Added new coordinate systems defined by LINZ standard LINZS25002.
Bug fix: Corrected error on orientation of plotted error ellipses.
Change: Removed script to add the SNAP program directory to the path, as this stops the installer running on Vista. Users wanting SNAP in the path will need to add this manually. Note that SNAP is in the path for the DOS box run from the snap_manager menu.
Bug fix: Fixed a problem with the snap_manager window disappearing to the background after running an adjustment.
Bug fix: Fixed a bug which disabled panning the map window.
Enhancement: Added option to choose font for plotting station names and codes.
Enhancement: Tidied up highight stations and hide stations dialog boxes.
Enhancement: Added the continue statement
Enhancement: Added more functions into the data files dialog based on scripts written by Jeremy Palmer
Enhancement: Split up configuration file into separate include files for main function areas
Bug fix: Fixed error in the precedence of the "." operator.
Documentation: Included documentation of the regular expression syntax
Bug fix: Fixed bug preventing calculation of geoid heights where input coordinate system was a projection coordinate system with a specified range.
Change: Changed Programs menu folder to be SNAP, rather than SNAP subfolder of LINZ folder.
Bug fix: Fixed bug whereby when plotting from data files (ie not from binary file), snapplot could not load projection bearings if not in the network coordinate system.
Bug fix: Fixed bug whereby when plotting from data files on a network drive snapplot fails with an error about not being able to create a binary file. This occurs because it was trying to create a temporary file on the root directory of the network drive.
Enhancement: Now adds SNAP installation directory to the path
Enhancement: Rationalised highlighting and hiding stations by error ellipses and height errors to use the current error options when testing against a threshold value.
New: Added the trvtest and gpstest SNAP configuration files to the build.
Enhancement: Added the ExecuteFuntion function to the scripting language. Added listbox to available items in a dialog box
Enhancement: Added plotting and editing data files to the menu
Enhancement: Changed all menu functions to be executed by functions, which can be overridden by local configuration, so that behaviours can be changed.
Enhancement: Added option of customising by included "*_menu.cfg" files in the scripts directory. These will be run as part of the startup configuration.
Enhancement: Tidied up many pages where formatting was particularly bad!
New: Added import from GDB function.
Enhancement: Added two string processing functions (Match, Replace), a date function (GetDate), an environment variable GetEnv() and a function to retrieve the value of a variable (GetValue) to the scripting language. Added (positive integer) numbers as unquoted strings.
Bug fix: Fixed New|SNAP file project. New project now uses a template file in the scripts directory.
Bug fix: Fixed errors in scripts where the coordinate file is not in the command file directory.
Bug fix: Fixed bug whereby accuracy tests not applied to the last station in test_specifications options
Bug fix: PNG image export now actually exports a .PNG file, not a .BMP file named xxx.png.
Bug fix: Snapplot locks the binary file so that adjustments cannot be rerun while snapplot is open. This avoids snapplot displaying corrupt data due to the binary file changing.
Change: Left clicking on the station or observation list highlights the station/observation on the map but doesn't show the details. To show details, double click on the station or observation.
Enhancement: Added more options to the highlight and hide/show stations dialog box.
Enhancement: Added a "find station" menu item for quickly looking up a station.
Enhancement: Incorporated station file coordinate orders into snapspec. Added options to base highest order tested on lowest order of control (-a), and to generate an updated coordinate file containing the revised orders (-u).
Enhancement: improved the layout of the descriptions of SNAP commands.
Enhancement: The format of the third line of the station coordinate file has been changed to a more general and clearer format. This consists of the keyword "options" followed by options specifying which station attributes are included in the file. Old format station coordinate files will be read without problem, but the generated coordinate files will have the new format header line. See coordinate file documentation.
Change: The format of the binary file is incompatible with previous versions. Binary files will need to be rebuilt by rerunning adjustments.
Enhancement: Added option to include station orders in coordinate file, and to include order=x in station lists in the command file
Enhancement: Rationallised the processing of geoid options in snapgeoid, and the processing of these in snapgeoid. The command line options for snapgeoid have been modified reflecting this .. see the snapgeoid documentation.
Enhancement: Added help button to dialog boxes
Enhancement: Restored Ctrl+Shift+Right click function of the DOS snapplot map to clear the station offset of a single station.
Enhancement: Rationallised the colour key and added an option for the selected station/observation colour to give full control of map colours
Enhancement: Added "order" to the station listing columns.
Enhancement: Added options to export map as an image (PNG or BMP), and reinstated the DXF export option (by popular demand!)
Enhancement: Added print map command to send the map to a printer
Enhancement: Add Copy menu for copying information from map and text windows to clipboard
Change: Renamed nzvd05.grd geoid model to more correct nzgeoid05, to distinguish between the geoid model and the vertical datum.
Enhancement: Calculation of deflections based upon geoid model, as well as undulations.
Add options to just list the stations in the data files, or to list the stations in the data files missing from the station file.
New: Added a new program snapmerge for merging station information from one coordinate file into another
Note: The hitherto undocumented scripting function has been updated in this version - any previous customisation may not work. This change does provide customisation options which will not be overwritten by new releases.
Enhancement: Scripting language enhanced to include dialog boxes.
Enhancement: Snap manager window is a little more informative ...
Enhancement: Configuration and scripting (briefly) documented
Change: Rationalised coordinate systems in the coordsys.def file. Commented out old codes for cadastral coordinate systems, as well as link systems, and duplicate codes for coordinate systems.
Bug fix: Help index wasn't working correctly. That has now been fixed
Bug fix: Fixed error causing snapplot to crash on exit when started without specifying a snap job to display
Bug fix: Fixed error when using right mouse button to go back through details text view whereby if after going back the mouse is still on a link the view returns back to the starting page.
Bug fix: Fixed bug that prevented controlling text colour
Bug fix: Fixed bug that caused error ellipses to sometimes be displayed with dashed lines
Enhancement: Added help file
Enhancement: Added option to change map background colour.
Enhancement: Fixed observations list to allow sorting on any column by clicking the column header. Changed the observation listing options to give more control and choices over columns listed.
Enhancement: Added a menu option for turning station offsets on or off
Enhancement: Added -g option to specify the name of a geoid or geoid file
Change: Changed the use of environment variables to select the geoid file to use. Now uses the GEOID to specify a geoid name or GEOIDBIN to specify a specific geoid file. Changed the default name from geoid.bin to geoid.grd
Change: Changed the use of environment variables to select the geoid file to use. Now uses the GEOID to specify a geoid name or GEOIDBIN to specify a specific geoid file. Changed the default name from geoid.bin to geoid.grd
Enhancement: SNAP manager program uses a scripting language to simplify future additions of functions, and to simplify customisations for LINZ/contractor use. This is still under development.
Bug fix: Fixed a bug that caused the last line on the plot to be not displayed. This was identified when a significant adjustment vector was not displayed
Enhancement: Reinstated the back function on details view. Right clicking the details window will revert to the previous details information. Up to 20 pages can be reversed. Note that this is a non conventional use of the right mouse button and may be changed in the future.
Enhancement: Allow observations to be turned off as well as coloured according the the category
Enhancement: Ensure that highlighted stations are always displayed over unhighlighted stations (this was already the case for observations)
Bug fix: Fixed a bug whereby snapspec was not able to find its default configuration file.