.\" This manpage is Copyright (C) 2016 MongoDB, Inc.
.\" 
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.\" under the terms of the GNU Free Documentation License, Version 1.3
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.TH "MONGOC_COLLECTION_COMMAND_SIMPLE" "3" "2016\(hy10\(hy12" "MongoDB C Driver"
.SH NAME
mongoc_collection_command_simple() \- This is a simplified version of mongoc_collection_command() that returns the first result document in reply. The parameter reply is initialized even upon failure to simplify memory management.
.SH "SYNOPSIS"

.nf
.nf
bool
mongoc_collection_command_simple (mongoc_collection_t       *collection,
                                  const bson_t              *command,
                                  const mongoc_read_prefs_t *read_prefs,
                                  bson_t                    *reply,
                                  bson_error_t              *error);
.fi
.fi

.SH "PARAMETERS"

.TP
.B
collection
A
.B mongoc_collection_t
.
.LP
.TP
.B
command
A
.B bson_t
containing the command to execute.
.LP
.TP
.B
read_prefs
An optional
.B mongoc_read_prefs_t
. Otherwise, the command uses mode
.B MONGOC_READ_PRIMARY
.
.LP
.TP
.B
reply
A location to initialize a
.B bson_t
. This should be on the stack.
.LP
.TP
.B
error
An optional location for a
.B bson_error_t
or
.B NULL
.
.LP

.SH "DESCRIPTION"

This is a simplified version of
.B mongoc_collection_command(3)
that returns the first result document in
.B reply
. The parameter
.B reply
is initialized even upon failure to simplify memory management.

This function tries to unwrap an embedded error in the command when possible. The unwrapped error will be propagated via the
.B error
parameter. Additionally, the result document is set in
.B reply
.

.SH "ERRORS"

Errors are propagated via the
.B error
parameter.

.SH "RETURNS"

.B true
if successful, otherwise
.B false
.

Not all commands have truly succeeded when
.B {ok:1.0}
is returned. This could simply mean the RPC successfully was executed.

.SH "EXAMPLE"

The following is an example of executing the collection stats command.

.nf
#include <mongoc.h>
#include <bcon.h>
#include <stdio.h>

static void
print_collection_stats (mongoc_collection_t *collection)
{
   bson_error_t error;
   const char *name;
   bson_t *cmd;
   bson_t reply;

   name = mongoc_collection_get_name (collection);
   cmd = BCON_NEW ("collStats", BCON_UTF8 (name));

   if (mongoc_collection_command_simple (collection, cmd, NULL, &reply, &error)) {
      str = bson_as_json (&reply, NULL);
      printf ("%s\en", str);
      bson_free (str);
   } else {
      fprintf (stderr, "%s\en", error.message);
   }

   bson_destroy (&reply);
   bson_destroy (cmd);
}
.fi


.B
.SH COLOPHON
This page is part of MongoDB C Driver.
Please report any bugs at https://jira.mongodb.org/browse/CDRIVER.