TOBIN User's Guide

Last revised on 2002 DEC 06 by B. V. Semenov.

Abstract

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

Summary

TOBIN is a utility program providing command line, or ``batch,'' oriented method for converting portable transfer files into SPICE binary kernel files. The name ``tobin'' is obviously derived from ``to binary,'' as in ``convert to binary''.

Particulars

TOBIN converts a SPICE transfer format file into it's binary format for use in a particular computing environment. TOBIN requires at least the name of the input transfer file, which is the first argument on the command line. Optionally, a name for the output binary file may be specified as the second argument on the command line. If a name for the output file is provided it overrides the automatic naming conventions used by the program.

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

TOBIN recognizes the transfer filename extensions ``.xc'', ``.xee'', ``.xpc'', and ``.xsp'' associated with transfer files for SPICE data products. These are converted to the SPICE binary kernel filename extensions ``.bc'', ``.bee'', ``.bpc'', and ``.bsp,'' respectively. Also recognized are the old transfer file extensions ``.tc'', ``.tee'', ``.tpc'', and ``.tsp,'' which are converted into the appropriate filename extensions for a binary kernel file.

Examples

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

   prompt > tobin thisfile.xsp

   prompt > tobin thisfile.xsp thisfile.bsp

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

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

            > tobin ephem.xsp

This will create the binary kernel file 'ephem.bsp'.

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

            > tobin ephem.xsp myephem.bsp

This will create the binary kernel file 'myephem.bsp'.

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

            > tobin mydata.ttt

This will create the binary file 'mydata.bin'.

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.