TOXFR User's Guide

Last revised on 2004 DEC 06 by B. V. Semenov.

Abstract

TOXFR is a command-line program that converts binary format SPK, CK and EK files to transfer format.

Summary

TOXFR is a utility program providing command line, or ``batch,'' oriented method for converting SPICE binary kernel files into portable transfer files. The name ``toxfr'' is, possibly not so obviously, derived from ``to transfer,'' as in ``convert to transfer.''

Particulars

TOXFR converts a SPICE binary kernel file into a transfer file format that is used to transfer, or port, the binary data to a different computing environment. TOXFR requires at least the name of the input binary file, which is the first argument on the command line. Optionally, a name for the output transfer file may be specified as the second argument on the command line. If a name for the output file is provided on the command line it overrides the automatic naming conventions used by the program.

If only the name of the input binary file is provided on the command line, TOXFR will generate a name for the output transfer file that has the same base name as the input binary file and an appropriate filename extension, based on the filename extension of the binary file. If TOXFR does not recognize the filename extension of the input binary file, or there is no filename extension on the input binary file, a filename extension of '.xfr' will be used as the filename extension of the output transfer file. If a file having the same name as the output file already exists, TOXFR signals an error and stops. Again, we assume that it is bad form to overwrite or replace an existing file.

TOXFR recognizes the filename extensions ``.bc'', ``.bee'', ``.bpc'', and ``.bsp'' which are associated with SPICE binary kernel files. These are converted to the transfer filename extensions ``.xc'', ``.xee'', ``.xpc'', and ``.xsp,'' respectively.

Examples

TOXFR requires the name of the file to be converted and, optionally, the name of the file to be produced, e.g.,

   prompt > toxfr thisfile.bsp

   prompt > toxfr thisfile.bsp thisfile.xsp

In the first example, the name for the transfer file produced is derived from the name of the binary file, using the full base name and replacing the letter `b' in the file name extension with the letter `x', to indicate that the file is a transfer file. In the second example, the name for the transfer file produced is taken directly from the command line.

-- Example 1: Convert the binary kernel file 'ephem.bsp' into a transfer file.

            > toxfr ephem.bsp

This will create the transfer file 'ephem.xsp'.

-- Example 2: This is the same as Example 1, except we explicitly set the output filename on the command line.

            > toxfr ephem.bsp myephem.xsp

This will create the transfer file 'myephem.xsp'.

-- Example 3: For this example, we provide a filename extension on the input binary file that TOXFR does not recognize.

            > toxfr mydata.bbb

This will create the transfer file 'mydata.xfr'.

Note about DAF Run-Time Binary File Format Translation

Starting with the N0052 release of the SPICE Toolkit (January, 2002) certain supported platforms are able to read DAF-based binary files (SPK, CK and binary PCK) that were written using a different, or non-native, binary representation. This capability eliminated the need to use transfer format to move DAF-based files between some of the platforms. Refer to the Convert User's Guide (convert.ug) to see if using transfer format files is indeed necessary in your data exchange path.