NAME

       bson_reader_t - bson_reader_t

       Streaming BSON Document Reader

SYNOPSIS

          #include <bson.h>

          typedef struct _bson_reader_t bson_reader_t;

          bson_reader_t *
          bson_reader_new_from_handle (void *handle,
                                       bson_reader_read_func_t rf,
                                       bson_reader_destroy_func_t df);
          bson_reader_t *
          bson_reader_new_from_fd (int fd, bool close_on_destroy);
          bson_reader_t *
          bson_reader_new_from_file (const char *path, bson_error_t *error);
          bson_reader_t *
          bson_reader_new_from_data (const uint8_t *data, size_t length);

          void
          bson_reader_destroy (bson_reader_t *reader);

DESCRIPTION

       bson_reader_t  is  a structure used for reading a sequence of BSON documents. The sequence
       can come from a file-descriptor, memory region, or custom callbacks.

EXAMPLE

          /*
           * Copyright 2013 MongoDB, Inc.
           *
           * Licensed under the Apache License, Version 2.0 (the "License");
           * you may not use this file except in compliance with the License.
           * You may obtain a copy of the License at
           *
           *   http://www.apache.org/licenses/LICENSE-2.0
           *
           * Unless required by applicable law or agreed to in writing, software
           * distributed under the License is distributed on an "AS IS" BASIS,
           * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
           * See the License for the specific language governing permissions and
           * limitations under the License.
           */

          /*
           * This program will print each BSON document contained in the provided files
           * as a JSON string to STDOUT.
           */

          #include <bson.h>
          #include <stdio.h>

          int
          main (int argc, char *argv[])
          {
             bson_reader_t *reader;
             const bson_t *b;
             bson_error_t error;
             const char *filename;
             char *str;
             int i;

             /*
              * Print program usage if no arguments are provided.
              */
             if (argc == 1) {
                fprintf (stderr, "usage: %s [FILE | -]...\nUse - for STDIN.\n", argv[0]);
                return 1;
             }

             /*
              * Process command line arguments expecting each to be a filename.
              */
             for (i = 1; i < argc; i++) {
                filename = argv[i];

                if (strcmp (filename, "-") == 0) {
                   reader = bson_reader_new_from_fd (STDIN_FILENO, false);
                } else {
                   if (!(reader = bson_reader_new_from_file (filename, &error))) {
                      fprintf (
                         stderr, "Failed to open \"%s\": %s\n", filename, error.message);
                      continue;
                   }
                }

                /*
                 * Convert each incoming document to JSON and print to stdout.
                 */
                while ((b = bson_reader_read (reader, NULL))) {
                   str = bson_as_canonical_extended_json (b, NULL);
                   fprintf (stdout, "%s\n", str);
                   bson_free (str);
                }

                /*
                 * Cleanup after our reader, which closes the file descriptor.
                 */
                bson_reader_destroy (reader);
             }

             return 0;
          }

AUTHOR

       MongoDB, Inc

COPYRIGHT

       2018, MongoDB, Inc