[netcdfgroup] crash in nc_get_vara

• To: netcdfgroup@xxxxxxxxxxxxxxxx
• Subject: [netcdfgroup] crash in nc_get_vara
• From: Ansley Manke <Ansley.B.Manke@xxxxxxxx>
• Date: Wed, 11 May 2011 10:48:02 -0700

Hi -

thanks -Ansley

/* test_vara_big.c  Crash on the call to nc_get_vara_float when the region is 
large. */
/* netcdf4.1.2, netcdf4.1.3beta and snapshots
/* 5/11/2011 */


#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <netcdf.h>

#define URL 
"http://ferret.pmel.noaa.gov/thredds/dodsC/data/PMEL/COADS/coads_air.cdf";

#define VAR "AIR"

#define X 180
#define Y 90
#define T 1680


/* A second example showing the same behavior.
/* #define URL 
"http://www.esrl.noaa.gov/psd/thredds/dodsC/Datasets/coads/1degree/global/enh/air.mean.nc";
/* 
/* #define VAR "air"
/* 
/* #define X 360
/* #define Y 180
/* #define T 616 */


#define RANK 3

#define ERRCODE 2
#define ERR(e) {printf("Error: %s\n", nc_strerror(e)); exit(ERRCODE);}

#undef DEBUG

static float threeD[T][Y][X];
static dims[RANK] = {T,Y,X};

/* Define whole variable start/count */
static size_t start0[RANK] = {0,0,0};
static size_t count0[RANK] = {T,Y,X};

int
main()
{
    int ncid, varid;
    int retval,i;
    size_t start[RANK];
    size_t count[RANK];
    
    memset((void*)threeD,0,sizeof(threeD));

    if((retval = nc_open(URL, NC_NOWRITE, &ncid)))
       ERR(retval);

    if((retval = nc_inq_varid(ncid, VAR, &varid)))
       ERR(retval);

    /* test 1: Read the first 100 timesteps */
    memcpy(start,start0,sizeof(start0));
    memcpy(count,count0,sizeof(count0));

        count[0] = 100;

    printf("*** read 100 timesteps\n");
    if((retval = nc_get_vara_float(ncid,varid,start,count,(float*)threeD)))
       ERR(retval);


    /* test 2: Read the whole variable */
    memcpy(start,start0,sizeof(start0));
    memcpy(count,count0,sizeof(count0));

    printf("*** read entire variable\n");
    if((retval = nc_get_vara_float(ncid,varid,start,count,(float*)threeD)))
       ERR(retval);

    if((retval = nc_close(ncid)))
       ERR(retval);

    return 0;
}

• References:
  • [netcdfgroup] Missing -lm and -lsz library issue
    • From: Chad Herman