Table of contents
kclear_c ( Keeper clear )
void kclear_c ( void )
Clear the KEEPER subsystem: unload all kernels, clear the kernel
pool, and re-initialize the subsystem. Existing watches on kernel
variables are retained.
VARIABLE I/O DESCRIPTION
-------- --- --------------------------------------------------
None. This routine operates by side effects. See -Particulars
1) If an error occurs when setting a kernel pool watch or
checking watched variables, the error is signaled by a routine
in the call tree of this routine.
This entry point allows you re-initialize the KEEPER system with
a single call. The KEEPER system is the kernel management system
underlying the set of CSPICE APIs
This routine unloads all kernels from their kernel-type-specific
kernel management subsystems (SPKBSR, CKBSR, etc.), clears the
kernel pool, clears KEEPER's internal file database, and re-sets
the watch status for the kernel variables used to load kernels
via meta-kernels. As a side effect of clearing the kernel pool,
all watched variables are marked as updated. Note that clearing
the kernel pool does not delete watchers.
This capability, though implemented in Fortran, is particularly
relevant to SPICE implementations such as Icy, for which the
state of the KEEPER system persists after any Icy-based IDL
script is run. Successive runs of Icy-based scripts may perform
in unexpected ways when scripts access data loaded during runs of
Cleaning up after such programs using explicit unload_c commands is
tedious and error-prone. One call to this routine sets the
KEEPER system to its initial state, preventing unintentional
interaction between scripts via KEEPER's state.
The numerical results shown for this example may differ across
platforms. The results depend on the SPICE kernels used as
input, the compiler and supporting libraries, and the machine
specific arithmetic implementation.
1) Load a meta-kernel containing three kernels, and count the
number of files in the kernel pool before and after calling
Use the meta-kernel shown below to load the required SPICE
File name: kclear_ex1.tm
This meta-kernel is intended to support operation of SPICE
example programs. The kernels shown here should not be
assumed to contain adequate or correct versions of data
required by SPICE-based user applications.
In order for an application to use this meta-kernel, the
kernels referenced here must be present in the user's
current working directory.
The names and contents of the kernels referenced
by this meta-kernel are as follows:
File name Contents
de421.bsp Planetary ephemeris
pck00008.tpc Planet orientation and
KERNELS_TO_LOAD = ( 'de421.bsp',
End of meta-kernel
Example code begins here.
Load the meta kernel.
furnsh_c( "kclear_ex1.tm" );
Count the number of loaded kernel files.
ktotal_c ( "ALL", &count );
printf ( "Count of loaded kernels before "
"kclear_c call: %d\n", count );
Clear the KEEPER system, retrieve the number of loaded
after the clear.
kclear_c ( );
ktotal_c ( "ALL", &count );
printf ( "Count of loaded kernels after "
"kclear_c call : %d\n", count );
When this program was executed on a Mac/Intel/cc/64-bit
platform, the output was:
Count of loaded kernels before kclear_c call: 4
Count of loaded kernels after kclear_c call : 0
1) Calling this routine will wipe out any kernel pool data
inserted via the CSPICE API routines to put data into the
kernel pool (pcpool_c, pdpool_c and pipool_c).
N.J. Bachman (JPL)
J. Diaz del Rio (ODC Space)
-CSPICE Version 1.0.2, 10-AUG-2021 (JDR)
Edited -Examples section to comply with NAIF standard. Added
Improved -Restrictions section.
-CSPICE Version 1.0.1, 01-JUL-2014 (NJB)
The header -Particulars section was updated to more
completely describe the effect of this routine on
kernel pool watchers. Header section order was corrected.
-CSPICE Version 1.0.0, 15-NOV-2006 (NJB)
Re-initialize the keeper system
Clear the keeper system
Unload all kernels