eccodes/examples/C/bufr_read_header.c

/*
 * Copyright 2005-2019 ECMWF.
 *
 * This software is licensed under the terms of the Apache Licence Version 2.0
 * which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
 *
 * In applying this licence, ECMWF does not waive the privileges and immunities granted to it by
 * virtue of its status as an intergovernmental organisation nor does it submit to any jurisdiction.
 */

/*
 * C Implementation: bufr_read_header
 *
 * Description: how to read the header of BUFR messages.
 *
 */

#include "eccodes.h"

static void usage(const char* prog)
{
    printf("usage: %s infile\n", prog);
    exit(1);
}

int main(int argc, char* argv[])
{
    char* filename = NULL;
    FILE* in       = NULL;

    /* message handle. Required in all the eccodes calls acting on a message.*/
    codes_handle* h = NULL;
    long longVal;
    int err = 0, cnt = 0;

    if (argc != 2) usage(argv[0]);

    filename = argv[1];

    in = fopen(filename, "rb");
    if (!in) {
        printf("ERROR: unable to open file %s\n", filename);
        return 1;
    }

    /* loop over the messages in the bufr file */
    while ((h = codes_handle_new_from_file(NULL, in, PRODUCT_BUFR, &err)) != NULL || err != CODES_SUCCESS) {
        if (h == NULL) {
            printf("Error: unable to create handle for message %d\n", cnt);
            cnt++;
            continue;
        }

        printf("message: %d\n", cnt);

        /* get and print some keys form the BUFR header */

        CODES_CHECK(codes_get_long(h, "dataCategory", &longVal), 0);
        printf("  dataCategory: %ld\n", longVal);

        CODES_CHECK(codes_get_long(h, "dataSubCategory", &longVal), 0);
        printf("  dataSubCategory: %ld\n", longVal);

        CODES_CHECK(codes_get_long(h, "typicalDate", &longVal), 0);
        printf("  typicalDate: %ld\n", longVal);

        CODES_CHECK(codes_get_long(h, "bufrHeaderCentre", &longVal), 0);
        printf("  bufrHeaderCentre: %ld\n", longVal);

        CODES_CHECK(codes_get_long(h, "bufrHeaderSubCentre", &longVal), 0);
        printf("  bufrHeaderSubCentre: %ld\n", longVal);

        CODES_CHECK(codes_get_long(h, "masterTablesVersionNumber", &longVal), 0);
        printf("  masterTablesVersionNumber: %ld\n", longVal);

        CODES_CHECK(codes_get_long(h, "localTablesVersionNumber", &longVal), 0);
        printf("  localTablesVersionNumber: %ld\n", longVal);

        CODES_CHECK(codes_get_long(h, "numberOfSubsets", &longVal), 0);
        printf("  numberOfSubsets: %ld\n", longVal);

        /* delete handle */
        codes_handle_delete(h);

        cnt++;
    }

    fclose(in);
    return 0;
}