| dashfs_c |
|
Table of contents
Procedure
dashfs_c ( DAS, handle to file summary )
void dashfs_c ( SpiceInt handle,
SpiceInt * nresvr,
SpiceInt * nresvc,
SpiceInt * ncomr,
SpiceInt * ncomc,
SpiceInt * free,
SpiceInt lastla [3],
SpiceInt lastrc [3],
SpiceInt lastwd [3] )
AbstractReturn a file summary for a specified DAS file. Required_ReadingDAS KeywordsDAS FILES Brief_I/OVARIABLE I/O DESCRIPTION -------- --- -------------------------------------------------- handle I Handle of a DAS file. nresvr O Number of reserved records in file. nresvc O Number of characters in use in reserved rec. area. ncomr O Number of comment records in file. ncomc O Number of characters in use in comment area. free O Number of first free record. lastla O Array of last logical addresses for each data type. lastrc O Record number of last descriptor of each data type. lastwd O Word number of last descriptor of each data type. Detailed_Input
handle is the handle of a previously opened DAS file. The file
may be open for read or write access.
Detailed_Output
nresvr is the number of reserved records in a specified DAS
file.
nresvc is the number of characters in use in the reserved record
area of a specified DAS file.
ncomr is the number of comment records in a specified DAS file.
ncomc is the number of characters in use in the comment area of
a specified DAS file.
free is the 1-based record number of the first free record in
a specified DAS file.
lastla is an array containing the highest current 1-based logical
addresses, in the specified DAS file, of data of
character, double precision, and integer types, in that
order.
lastrc is an array containing the 1-based record numbers, in the
specified DAS file, of the directory records containing
the current last descriptors of clusters of character,
double precision, and integer data records, in that
order.
lastwd is an array containing the 1-based word indices, within
the respective descriptor records identified by the
elements of `lastrc', of the current last descriptors of
clusters of character, double precision, and integer data
records, in that order.
Parameters
See header file SpiceDAS.h for declarations and descriptions of
parameters used throughout the DAS system.
SPICE_DAS_CHARDT,
SPICE_DAS_DPDT,
SPICE_DAS_INTDT
are data type specifiers which indicate SpiceChar,
SpiceDouble, and SpiceInt respectively. These
parameters are used in all DAS routines that require a
data type specifier.
Exceptions
1) If the specified handle does not belong to any file that is
currently known to be open, the error SPICE(DASNOSUCHHANDLE)
is signaled by a routine in the call tree of this routine.
FilesNone. Particulars
The quantities
nresvr
nresvc
ncomr
ncomc
free
lastla
lastrc
lastwd
define the "state" of a DAS file, and in particular the state of
the directory structure of the file. This information is needed by
other DAS routines, but application programs will usually have no
need for it. The one exception is the array of "last" logical
addresses `lastla': these addresses indicate how many words of data
of each type are contained in the specified DAS file. The elements
of `lastla' can be conveniently retrieved by calling daslla_c.
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) Create a DAS file containing 10 integers, 5 double precision
numbers, and 4 characters. Print the summary of the file and
dump its contents.
Example code begins here.
/.
Program dashfs_ex1
./
#include <stdio.h>
#include <string.h>
#include "SpiceUsr.h"
int main( )
{
/.
Local parameters.
./
#define FNAME "dashfs_ex1.das"
#define LINLEN 2
/.
Local variables.
./
ConstSpiceChar * ifname;
ConstSpiceChar * type;
SpiceChar line [LINLEN];
SpiceChar linstr [LINLEN+1];
SpiceDouble dbli;
SpiceDouble x;
SpiceInt first;
SpiceInt free;
SpiceInt handle;
SpiceInt i;
SpiceInt last;
SpiceInt lastla [3];
SpiceInt lastrc [3];
SpiceInt lastwd [3];
SpiceInt n;
SpiceInt ncomc;
SpiceInt ncomr;
SpiceInt nread;
SpiceInt nresvc;
SpiceInt nresvr;
SpiceInt remain;
/.
Open a new DAS file. Reserve no records for comments.
./
type = "TEST";
ifname = "TEST.DAS/NAIF/NJB/11-NOV-1992-20:12:20";
dasonw_c ( FNAME, type, ifname, 0, &handle );
/.
Obtain the file summary.
./
dashfs_c ( handle, &nresvr, &nresvc,
&ncomr, &ncomc, &free,
lastla, lastrc, lastwd );
/.
Print the summary of the new file.
./
printf( "Summary before adding data:\n" );
printf( " Number of reserved records : %d\n", (int)nresvr );
printf( " Characters in reserved records : %d\n", (int)nresvc );
printf( " Number of comment records : %d\n", (int)ncomr );
printf( " Characters in comment area : %d\n", (int)ncomc );
printf( " Number of first free record : %d\n", (int)free );
printf( " Last logical character address : %d\n",
(int)lastla[SPICE_DAS_CHARDT] );
printf( " Last logical d.p. address : %d\n",
(int)lastla[SPICE_DAS_DPDT] );
printf( " Last logical integer address : %d\n",
(int)lastla[SPICE_DAS_INTDT] );
printf( " Last character descriptor : %d\n",
(int)lastrc[SPICE_DAS_CHARDT] );
printf( " Last d.p descriptor : %d\n",
(int)lastrc[SPICE_DAS_DPDT] );
printf( " Last integer descriptor : %d\n",
(int)lastrc[SPICE_DAS_INTDT] );
printf( " Character word position in desc: %d\n",
(int)lastwd[SPICE_DAS_CHARDT] );
printf( " d.p. word position in desc : %d\n",
(int)lastwd[SPICE_DAS_DPDT] );
printf( " Integer word position in desc : %d\n",
(int)lastwd[SPICE_DAS_INTDT] );
printf( "\n" );
/.
Add the data.
./
for ( i = 1; i < 11; i++ )
{
dasadi_c ( handle, 1, &i );
}
for ( i = 1; i < 6; i++ )
{
dbli = (double)i;
dasadd_c ( handle, 1, &dbli );
}
/.
Add character data to the file. DAS character data are
treated as a character array, not as a null-terminated
string. The following call adds only the first 4 characters
to the DAS file.
./
dasadc_c ( handle, 4, 0, 3, 4, "SPUDWXY" );
/.
Close the file and open it for reading.
./
dascls_c ( handle );
dasopr_c ( FNAME, &handle );
/.
Obtain again the file summary.
./
dashfs_c ( handle, &nresvr, &nresvc,
&ncomr, &ncomc, &free,
lastla, lastrc, lastwd );
printf( "Summary after adding data:\n" );
printf( " Number of reserved records : %d\n", (int)nresvr );
printf( " Characters in reserved records : %d\n", (int)nresvc );
printf( " Number of comment records : %d\n", (int)ncomr );
printf( " Characters in comment area : %d\n", (int)ncomc );
printf( " Number of first free record : %d\n", (int)free );
printf( " Last logical character address : %d\n",
(int)lastla[SPICE_DAS_CHARDT] );
printf( " Last logical d.p. address : %d\n",
(int)lastla[SPICE_DAS_DPDT] );
printf( " Last logical integer address : %d\n",
(int)lastla[SPICE_DAS_INTDT] );
printf( " Last character descriptor : %d\n",
(int)lastrc[SPICE_DAS_CHARDT] );
printf( " Last d.p descriptor : %d\n",
(int)lastrc[SPICE_DAS_DPDT] );
printf( " Last integer descriptor : %d\n",
(int)lastrc[SPICE_DAS_INTDT] );
printf( " Character word position in desc: %d\n",
(int)lastwd[SPICE_DAS_CHARDT] );
printf( " d.p. word position in desc : %d\n",
(int)lastwd[SPICE_DAS_DPDT] );
printf( " Integer word position in desc : %d\n",
(int)lastwd[SPICE_DAS_INTDT] );
printf( "\n" );
/.
Read the integers and dump them.
./
printf( "Integer data in the DAS file:\n" );
for ( i = 1; i <= lastla[SPICE_DAS_INTDT]; i++ )
{
dasrdi_c ( handle, i, i, &n );
printf( " %d\n", (int)n );
}
/.
Now the d.p. numbers:
./
printf( "\n" );
printf( "Double precision data in the DAS file:\n" );
for ( i = 1; i <= lastla[SPICE_DAS_DPDT]; i++ )
{
dasrdd_c ( handle, i, i, &x );
printf( " %f\n", x );
}
/.
Now the characters. In this case, we read the
data one line at a time.
./
first = 0;
last = 0;
remain = lastla[SPICE_DAS_CHARDT];
printf( "\n" );
printf( "Character data in the DAS file:\n" );
while ( remain > 0 )
{
nread = mini_c( 2, LINLEN, remain );
first = last + 1;
last = last + nread;
dasrdc_c ( handle, first, last, 0, nread-1, LINLEN, line );
/.
Add null-terminating character to `line' in order to
print it to the screen.
./
strncpy( linstr, line, LINLEN );
linstr[LINLEN] = '\0';
printf( " %s\n", linstr );
remain = remain - nread;
}
/.
Close the file.
./
dascls_c ( handle );
return ( 0 );
}
When this program was executed on a Mac/Intel/cc/64-bit
platform, the output was:
Summary before adding data:
Number of reserved records : 0
Characters in reserved records : 0
Number of comment records : 0
Characters in comment area : 0
Number of first free record : 3
Last logical character address : 0
Last logical d.p. address : 0
Last logical integer address : 0
Last character descriptor : 0
Last d.p descriptor : 0
Last integer descriptor : 0
Character word position in desc: 0
d.p. word position in desc : 0
Integer word position in desc : 0
Summary after adding data:
Number of reserved records : 0
Characters in reserved records : 0
Number of comment records : 0
Characters in comment area : 0
Number of first free record : 6
Last logical character address : 4
Last logical d.p. address : 5
Last logical integer address : 10
Last character descriptor : 2
Last d.p descriptor : 2
Last integer descriptor : 2
Character word position in desc: 10
d.p. word position in desc : 11
Integer word position in desc : 12
Integer data in the DAS file:
1
2
3
4
5
6
7
8
9
10
Double precision data in the DAS file:
1.000000
2.000000
3.000000
4.000000
5.000000
Character data in the DAS file:
SP
UD
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, 16-JUL-2021 (JDR) Index_Entriesreturn the file summary of a DAS file find the amount of data in a DAS file |
Fri Dec 31 18:41:03 2021