1MONGOC_COLLECTION_WATCH(3)     MongoDB C Driver     MONGOC_COLLECTION_WATCH(3)
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NAME

6       mongoc_collection_watch - mongoc_collection_watch()
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SYNOPSIS

9          mongoc_change_stream_t*
10          mongoc_collection_watch (const mongoc_collection_t *coll,
11                                   const bson_t *pipeline,
12                                   const bson_t *opts);
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14       A  helper  function  to create a change stream. It is preferred to call
15       this function over using a raw aggregation to create a change stream.
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17       This function uses the read preference and read concern of the  collec‐
18       tion.  If  the change stream needs to re-establish connection, the same
19       read preference will be used. This may  happen  if  the  change  stream
20       encounters a resumable error.
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22       WARNING:
23          A change stream is only supported with majority read concern.
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PARAMETERS

26       · coll:  A  mongoc_collection_t  specifying  the  collection  which the
27         change stream listens to.
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29       · pipeline: A bson_t representing an aggregation pipeline  appended  to
30         the change stream. This may be an empty document.
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32       · opts: A bson_t containing change stream options or NULL.
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34       opts  may be NULL or a document consisting of any subset of the follow‐
35       ing parameters:
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37       · batchSize An int32 representing number of documents requested  to  be
38         returned on each call to mongoc_change_stream_next
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40       · resumeAfter A Document representing the logical starting point of the
41         change stream. The _id field  of any change received  from  a  change
42         stream can be used here.
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44       · startAtOperationTime  A  Timestamp.  The  change stream only provides
45         changes that occurred at or after the specified timestamp.  Any  com‐
46         mand run against the server will return an operation time that can be
47         used here.
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49       · maxAwaitTimeMS An int64 representing the maximum  amount  of  time  a
50         call to mongoc_change_stream_next will block waiting for data
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52       · collation A Collation Document
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RETURNS

55       A  newly allocated mongoc_change_stream_t which must be freed with mon‐
56       goc_change_stream_destroy when no longer  in  use.  The  returned  mon‐
57       goc_change_stream_t  is  never  NULL.  If  there is an error, it can be
58       retrieved  with  mongoc_change_stream_error_document,  and   subsequent
59       calls to mongoc_change_stream_next will return false.
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SEE ALSO

62       mongoc_client_watch
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64       mongoc_database_watch
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AUTHOR

67       MongoDB, Inc
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70       2017-present, MongoDB, Inc
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751.13.1                           Jan 24, 2019       MONGOC_COLLECTION_WATCH(3)
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