eccodes/examples/examples.dev/keys_iterator.c

94 lines
1.9 KiB
C

/*
* C Implementation: keys_iterator
*
* Description:
* Example on how to use keys_iterator functions and the
* grib_keys_iterator structure to get all the available
* keys in a message.
*
*
*
* Author: Enrico Fucile <enrico.fucile@ecmwf.int>, (C) 2006
*
* Copyright: See COPYING file that comes with this distribution
*
*/
#include <assert.h>
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include "grib_api.h"
#define MAX_KEY_LEN 255
#define MAX_VAL_LEN 1024
static void usage(char* progname);
int main(int argc, char *argv[])
{
/* filter out keys from the key_iterator with
* key_iterator_filter_flags -> GRIB_NO_READ_ONLY_KEYS, GRIB_NO_OPTIONAL_KEYS
* set it to 0 if you want all keys
*/
/* unsigned long key_iterator_filter_flags=GRIB_KEYS_ITERATOR_SKIP_READ_ONLY || GRIB_KEYS_ITERATOR_SKIP_OPTIONAL; */
unsigned long key_iterator_filter_flags=GRIB_KEYS_ITERATOR_ALL_KEYS;
/* char* namespace=0; */
char* namespace="mars";
FILE* f;
grib_handle* h=NULL;
grib_keys_iterator* kiter=NULL;
int err=0;
int grib_count=0;
char value[MAX_VAL_LEN];
size_t vlen=MAX_VAL_LEN;
if (argc != 2) usage(argv[0]);
f = fopen(argv[1],"r");
if(!f) {
perror(argv[1]);
exit(1);
}
while((h = grib_handle_new_from_file(0,f,&err)) != NULL) {
grib_count++;
printf("-- GRIB N. %d --\n",grib_count);
if(!h) {
printf("ERROR: Unable to create grib handle\n");
exit(1);
}
kiter=grib_keys_iterator_new(h,key_iterator_filter_flags,namespace);
if (!kiter) {
printf("ERROR: Unable to create keys iterator\n");
exit(1);
}
while(grib_keys_iterator_next(kiter))
{
const char* name = grib_keys_iterator_get_name(kiter);
vlen=MAX_VAL_LEN;
GRIB_CHECK(grib_keys_iterator_get_string(kiter,value,&vlen),name);
printf("%s = %s\n",name,value);
}
grib_keys_iterator_delete(kiter);
}
return 0;
}
static void usage(char* progname) {
printf("\nUsage: %s grib_file\n",progname);
exit(1);
}