void unload_c ( ConstSpiceChar * file )
Unload a SPICE kernel.
VARIABLE I/O DESCRIPTION
-------- --- --------------------------------------------------
file I The name of a kernel to unload.
file is the name of a file to unload. This file
should be one loaded through the interface furnsh_c.
If the file is not on the list of loaded kernels
no action is taken.
Note that if file is a meta-text kernel, all of
the files loaded as a result of loading the meta-text
kernel will be unloaded.
1) If the specified kernel is not on the list of loaded kernels
no action is taken.
2) If the input file argument pointer is null, the error
SPICE(NULLPOINTER) will be signaled.
3) If the input file argument pointer is the empty string, the error
SPICE(EMPTYSTRING) will be signaled.
unload_c ( file );
has the effect of "erasing" the last previous call:
furnsh_c ( file );
This interface allows you to unload binary and text kernels.
Moreover, if you used a meta-text kernel to set up your
working environment, you can unload all of the kernels loaded
through the meta-kernel by unloading the meta-kernel.
Unloading Text or Meta-text Kernels.
Part of the action of unloading text (or meta-text kernels) is
clearing the kernel pool and re-loading any kernels that were not in
the specified set of kernels to unload. Since loading of text
kernels is not a very fast process, unloading text kernels takes
considerably longer than unloading binary kernels. Moreover, since
the kernel pool is cleared, any kernel pool variables you have set
from your program by using one of the interfaces pcpool_c, pdpool_c,
pipool_c, or lmpool_c will be removed from the kernel pool. For
this reason, if you plan to use this feature in your program,
together with one of the routines specified above, you will need to
take special precautions to make sure kernel pool variables required
by your program do not inadvertently disappear.
Suppose that you wish to compare two different sets of kernels
used to describe the geometry of a mission (for example a predict
model and a reconstructed model). You can place all of the
kernels for one model in one meta-text kernel, and the other set
in a second meta-text kernel. Let's call these predict.mta and
furnsh_c ( "predct.mta" );
Compute quantities of interest and store them
for comparison with results of reconstructed
Now unload the predict model and load the reconstructed
unload_c ( "predct.mta" );
furnsh_c ( "actual.mta" );
Re-compute quantities of interest and compare them
with the stored quantities.
See the note regarding the unloading of text and meta-text
N.J. Bachman (JPL)
W.L. Taber (JPL)
-CSPICE Version 1.0.0, 01-SEP-1999 (NJB) (WLT)
Unload a SPICE kernel