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Bug with nc_inq_varid() in C interface?

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  • Subject: Bug with nc_inq_varid() in C interface?
  • Date: Tue, 02 Aug 2005 09:46:18 -0600
Thomas,

> Anyway, I'm using the C interface inside my C++ class now, as I'm
> more sure (now) about what happens there (although it's not nice
> that it segfaults when trying to get the id to a non-existent
> variable name instead of just indicating an error...).

I can't reproduce this problem.  Could you try compiling and running
the small C program I have appended to the end of this message?  It
just tries to get the id of a variable named "no_such_variable" from
whatever netCDF file is named as its command-line argument.

When I run it, the output is as expected:

  $ ./varname test.nc
  line 24 of varname.c: Variable not found

rather than a segfault.  If you get a segfault, there must be
something wrong with your netCDF installation.  In that case, please
let us know what version you have installed and if you built from
source, whether you ran "make test" after building the library.

--Russ

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

void
check_err(const int stat, const int line, const char *file) {
    if (stat != NC_NOERR) {
           (void) fprintf(stderr, "line %d of %s: %s\n", 
                          line, file, nc_strerror(stat));
        exit(1);
    }
}

int
main(int argc, char *args[]) {  /* test nc_inq_varid for non-existent variable 
*/
   int  ncid, varid, stat;                      
   stat = nc_open(args[1], NC_NOWRITE, &ncid);
   check_err(stat,__LINE__,__FILE__);
   stat = nc_inq_varid(ncid, "no_such_variable", &varid);
   check_err(stat,__LINE__,__FILE__);
   (void) printf("Should never get here\n");
   return 0;
}