/* This program adds two new variables to an existing netCDF file.
 * It is used to test if netCDF can correctly calculate the file offsets
 * for the two new variables, in particular for files that align the
 * fix-size variables to a boundary larger than 4 bytes, for instance
 * a file created by PnetCDF with defaut alignment of 512 bytes.
 *
 * To check the file offsets for all variables, adding a printf statement is
 * necessary in netcdf-4.3.3.1/libsrc/nc3internal.c around line 222,
 * for example,
 * printf("var %s: begin=%ld len=%ld end=%ld\n",(*vpp)->name->cp, (*vpp)->begin, (*vpp)->len, (*vpp)->begin+(*vpp)->len);
 *
 * Check the first new variable's begin to see whether it is less than
 * the last variable's offset in the existing file.
 */
#include <stdio.h>
#include <stdlib.h>
#include <netcdf.h>

#define ERR {if(err!=NC_NOERR){printf("Error at line=%d: %s\n", __LINE__, nc_strerror(err));}}

int main(int argc, char** argv) {
    int err, ncid, varid[2], dimid[2];

    if (argc != 2) {
        printf("Usage: %s [filename]\n",argv[0]);
        exit(1);
    }

    err = nc_open(argv[1], NC_WRITE, &ncid); ERR
    err = nc_redef(ncid); ERR

    /* add 2 new dimensions */
    err = nc_def_dim(ncid, "new_dim_1", 5, &dimid[0]); ERR
    err = nc_def_dim(ncid, "new_dim_2", 4, &dimid[1]); ERR

    /* add 2 new dimensions */
    err = nc_def_var(ncid, "new_var1", NC_INT,   2, dimid, &varid[0]); ERR
    err = nc_def_var(ncid, "new_var2", NC_FLOAT, 2, dimid, &varid[1]); ERR
    err = nc_enddef(ncid); ERR
    err = nc_close(ncid); ERR

    return 0;
}