Provided by: libmongoc-doc_2.2.0-1_all 
SYNOPSIS
bool
mongoc_client_read_write_command_with_opts (
mongoc_client_t *client,
const char *db_name,
const bson_t *command,
const mongoc_read_prefs_t *read_prefs /* UNUSED */,
const bson_t *opts,
bson_t *reply,
bson_error_t *error);
Execute a command on the server, applying logic for commands that both read and write, and taking the
MongoDB server version into account. To send a raw command to the server without any of this logic, use
mongoc_client_command_simple() <>.
Use this function for commands that both read and write, such as "mapReduce" with an output collection.
Read and write concern and collation can be overridden by various sources. In a transaction, read concern
and write concern are prohibited in opts. The highest-priority sources for these options are listed first
in the following table. Read preferences are not applied. The write concern is omitted for MongoDB before
3.4.
┌──────────────┬───────────────┬───────────┐
│ Read Concern │ Write Concern │ Collation │
├──────────────┼───────────────┼───────────┤
│ opts │ opts │ opts │
├──────────────┼───────────────┼───────────┤
│ Transaction │ Transaction │ │
├──────────────┼───────────────┼───────────┤
│ client │ client │ │
└──────────────┴───────────────┴───────────┘
See the example for transactions <#mongoc-client-session-start-transaction-example> and for the
"distinct" command with opts <#mongoc-client-read-command-with-opts-example>.
reply is always initialized, and must be freed with bson_destroy() <https://www.mongoc.org/libbson/
current/bson_destroy.html>.
(The mongoc_read_prefs_t <> parameter was included by mistake when this function was introduced in
libmongoc 1.5. A command that writes must not obey a read preference.)
PARAMETERS
• client: A mongoc_client_t <>.
• db_name: The name of the database to run the command on.
• command: A bson_t <https://www.mongoc.org/libbson/current/bson_t.html> containing the command
specification.
• read_prefs: Ignored.
• opts: A bson_t <https://www.mongoc.org/libbson/current/bson_t.html> containing additional options.
• reply: A maybe-NULL pointer to overwritable storage <https://www.mongodb.com/docs/languages/c/c-driver/
current/libbson/guides/lifetimes/#overwritable-storage> for a bson_t <https://www.mongoc.org/libbson/
current/bson_t.html> to contain the results.
• error: An optional location for a bson_error_t <> or NULL.
opts may be NULL or a BSON document with additional command options:
• readConcern: Construct a mongoc_read_concern_t <> and use mongoc_read_concern_append() <> to add the
read concern to opts. See the example code for mongoc_client_read_command_with_opts() <>. Read concern
requires MongoDB 3.2 or later, otherwise an error is returned.
• writeConcern: Construct a mongoc_write_concern_t <> and use mongoc_write_concern_append() <> to add the
write concern to opts. See the example code for mongoc_client_write_command_with_opts() <>.
• sessionId: First, construct a mongoc_client_session_t <> with mongoc_client_start_session() <>. You can
begin a transaction with mongoc_client_session_start_transaction() <>, optionally with a
mongoc_transaction_opt_t <> that overrides the options inherited from client, and use
mongoc_client_session_append() <> to add the session to opts. See the example code for
mongoc_client_session_t <>.
• collation: Configure textual comparisons. See Setting Collation Order <https://www.mongodb.com/docs/
languages/c/c-driver/current/libmongoc/guides/bulk/#setting-collation-order>, and the MongoDB Manual
entry on Collation <https://www.mongodb.com/docs/manual/reference/collation/>. Collation requires
MongoDB 3.2 or later, otherwise an error is returned.
• serverId: To target a specific server, include an int32 "serverId" field. Obtain the id by calling
mongoc_client_select_server() <>, then mongoc_server_description_id() <> on its return value.
Consult the MongoDB Manual entry on Database Commands <https://www.mongodb.com/docs/manual/reference/
command/> for each command's arguments.
ERRORS
Errors are propagated via the error parameter.
RETURNS
Returns true if successful. Returns false and sets error if there are invalid arguments or a server or
network error.
A write concern timeout or write concern error is considered a failure.
EXAMPLE
See the example code for mongoc_client_read_command_with_opts() <>.
Author
MongoDB, Inc
Copyright
2009-present, MongoDB, Inc.
2.2.0 Nov 26, 2025 MONGOC_CLIENT_READ_WRITE_COMMAND_WITH_OPTS(3)