| dasllc_c |
|
Table of contents
Proceduredasllc_c ( DAS, low-level close ) void dasllc_c ( SpiceInt handle ) AbstractClose the DAS file associated with a given handle, without flushing buffered data or segregating the file. Required_ReadingDAS KeywordsDAS FILES Brief_I/OVARIABLE I/O DESCRIPTION -------- --- -------------------------------------------------- handle I Handle of a DAS file to be closed. Detailed_Inputhandle is the handle of a previously opened DAS file. Detailed_OutputNone. See -Particulars for a description of the effect of this routine. ParametersNone. Exceptions
1) If the specified handle does not belong to a DAS file that is
currently open, this routine returns without signaling an
error.
FilesSee the description of the argument `handle' in -Detailed_Input. ParticularsNormally, routines outside of CSPICE will not need to call this routine. Application programs should close DAS files by calling the CSPICE routine dascls_c. This routine is a lower-level routine that is called by dascls_c, but (obviously) does not have the full functionality of dascls_c. This routine closes a DAS file and updates the DAS file manager's bookkeeping information on open DAS files. Because the DAS file manager must keep track of which files are open at any given time, it is important that DAS files be closed only with dascls_c or dasllc_c, to prevent the remaining DAS routines from failing, sometimes mysteriously. Note that when a file is opened more than once for read or write access, dasopr_c returns the same handle each time it is re-opened. Each time the file is closed, dasllc_c checks to see if any other claims on the file are still active before physically closing the file. Unlike dascls_c, this routine does not force a write of updated, buffered records to the indicated file, nor does it segregate the data records in the file. Examples
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) Write a DAS file by adding data to it over multiple passes.
Avoid spending time on file segregation between writes.
Each pass opens the file, adds character, double precision,
and integer data to the file, writes out buffered data by
calling daswbr_c, and closes the file without segregating the
data by calling dasllc_c.
The program also checks the file: after the final write,
the program reads the data and compares it to expected values.
Note that most user-oriented applications should segregate a
DAS file after writing it, since this greatly enhances file
reading efficiency. The technique demonstrated here may be
useful for cases in which a file will be written via many
small data additions, and in which the file is read between
write operations.
Example code begins here.
/.
Program dasllc_ex1
./
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "SpiceUsr.h"
int main( )
{
/.
Local parameters
./
#define CHRLEN 50
#define IBUFSZ 20
#define DBUFSZ 30
/.
Local variables
./
SpiceChar chrbuf [CHRLEN];
SpiceChar chrstr [CHRLEN+1];
SpiceChar xchrbf [CHRLEN+1];
SpiceDouble dpbuf [DBUFSZ];
SpiceDouble xdpbuf [DBUFSZ];
SpiceInt firstc;
SpiceInt firstd;
SpiceInt firsti;
SpiceInt handle;
SpiceInt i;
SpiceInt intbuf [IBUFSZ];
SpiceInt j;
SpiceInt lastc;
SpiceInt lastd;
SpiceInt lasti;
SpiceInt passno;
SpiceInt xintbf [IBUFSZ];
/.
Initial values
./
ConstSpiceChar * fname = "dasllc_ex1.das";
ConstSpiceChar * ftype = "ANG";
SpiceInt ncall = 1000;
SpiceInt ncomr = 10;
SpiceInt npass = 3;
/.
Open a new DAS file. We'll allocate `ncomr' records
for comments. The file type is not one of the standard
types recognized by SPICE; however it can be used to
ensure the database file is of the correct type.
We'll use the file name as the internal file name.
./
dasonw_c ( fname, ftype, fname, ncomr, &handle );
/.
Add data of character, integer, and double precision
types to the file in interleaved fashion. We'll add to
the file over `npass' "passes," in each of which we close
the file after writing.
./
for ( passno = 1; passno <= npass; passno++ )
{
if ( passno > 1 )
{
printf( "Opening file for write access...\n" );
dasopw_c ( fname, &handle );
}
for ( i = 1; i <= ncall; i++ )
{
/.
Add string data to the file.
./
strncpy( chrbuf, "Character value #", 18 );
repmi_c ( chrbuf, "#", i, CHRLEN, chrbuf );
dasadc_c ( handle, CHRLEN, 0, CHRLEN-1, CHRLEN, chrbuf );
/.
Add double precision data to the file.
./
for ( j = 1; j <= DBUFSZ; j++ )
{
dpbuf[j-1] = (SpiceDouble)( 100000000*passno + 100*i + j );
}
dasadd_c ( handle, DBUFSZ, dpbuf );
/.
Add integer data to the file.
./
for ( j = 1; j <= IBUFSZ; j++ )
{
intbuf[j-1] = 100000000*passno + 100 * i + j;
}
dasadi_c ( handle, IBUFSZ, intbuf );
}
/.
Write buffered data to the file.
./
printf( "Writing buffered data...\n" );
daswbr_c ( handle );
/.
Close the file without segregating it.
./
printf( "Closing DAS file...\n" );
dasllc_c ( handle );
}
printf( "File write is done.\n" );
/.
Check file contents.
./
dasopr_c ( fname, &handle );
/.
Read data from the file; compare to expected values.
Initialize end addresses.
./
lastc = 0;
lastd = 0;
lasti = 0;
for ( passno = 1; passno <= npass; passno++ )
{
for ( i = 1; i <= ncall; i++ )
{
/.
Check string data.
./
strncpy( xchrbf, "Character value #", 18 );
repmi_c ( xchrbf, "#", i, CHRLEN+1, xchrbf );
firstc = lastc + 1;
lastc = lastc + CHRLEN;
dasrdc_c ( handle, firstc, lastc, 0,
CHRLEN-1, CHRLEN, chrbuf );
if ( strncmp( chrbuf, xchrbf, CHRLEN ) )
{
/.
Add null-terminating character to `chrbuf' in order to
print it to the screen.
./
strncpy( chrstr, chrbuf, CHRLEN );
chrstr[CHRLEN] = '\0';
printf( "Character data mismatch:\n" );
printf( "PASS = %d\n", (int)passno );
printf( "I = %d\n", (int)i );
printf( "Expected = %s\n", xchrbf );
printf( "Actual = %s\n", chrstr );
exit( EXIT_FAILURE );
}
/.
Check double precision data.
./
for ( j = 1; j <= DBUFSZ; j++ )
{
xdpbuf[j-1] = (SpiceDouble)( 100000000*passno + 100*i + j );
}
firstd = lastd + 1;
lastd = lastd + DBUFSZ;
dasrdd_c ( handle, firstd, lastd, dpbuf );
for ( j = 0; j < DBUFSZ; j++ )
{
if ( dpbuf[j] != xdpbuf[j] )
{
printf( "Double precision data mismatch:\n" );
printf( "PASS = %d\n", (int)passno );
printf( "I = %d\n", (int)i );
printf( "J = %d\n", (int)j );
printf( "Expected = %f\n", xdpbuf[j] );
printf( "Actual = %f\n", dpbuf[j] );
exit( EXIT_FAILURE );
}
}
/.
Check integer data.
./
for ( j = 1; j <= IBUFSZ; j++ )
{
xintbf[j-1] = 100000000*passno + 100 * i + j;
}
firsti = lasti + 1;
lasti = lasti + IBUFSZ;
dasrdi_c ( handle, firsti, lasti, intbuf );
for ( j = 0; j < IBUFSZ; j++ )
{
if ( intbuf[j] != xintbf[j] )
{
printf( "Integer data mismatch:\n" );
printf( "PASS = %d\n", (int)passno );
printf( "I = %d\n", (int)i );
printf( "J = %d\n", (int)j );
printf( "Expected = %d\n", xintbf[j] );
printf( "Actual = %d\n", intbuf[j] );
exit( EXIT_FAILURE );
}
}
}
}
printf( "File check is done.\n" );
/.
Close the file.
./
dascls_c ( handle );
return ( 0 );
}
When this program was executed on a Mac/Intel/cc/64-bit
platform, the output was:
Writing buffered data...
Closing DAS file...
Opening file for write access...
Writing buffered data...
Closing DAS file...
Opening file for write access...
Writing buffered data...
Closing DAS file...
File write is done.
File check is done.
Note that after run completion, a new DAS file exists in the
output directory.
RestrictionsNone. Literature_ReferencesNone. Author_and_InstitutionJ. Diaz del Rio (ODC Space) Version-CSPICE Version 1.0.0, 23-FEB-2021 (JDR) Index_Entriesclose a DAS file |
Fri Dec 31 18:41:03 2021