---
name: "mongoc_collection_find_and_modify"
section: "3"
platform: "linux"
package: "libmongoc-doc"
version: "1.30.4-1+deb13u3"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/mongoc_collection_find_and_modify"
---

# mongoc\_collection\_find\_and\_modify(3)

## SYNOPSIS

```
bool
mongoc_collection_find_and_modify (mongoc_collection_t *collection,
                                   const bson_t *query,
                                   const bson_t *sort,
                                   const bson_t *update,
                                   const bson_t *fields,
                                   bool _remove,
                                   bool upsert,
                                   bool _new,
                                   bson_t *reply,
                                   bson_error_t *error);
```

## PARAMETERS

- •

  **collection**: A *mongoc\_collection\_t*.

- •

  **query**: A *bson\_t* containing the query to locate target document(s).

- •

  **sort**: A *bson\_t* containing the sort order for **query**.

- •

  **update**: A *bson\_t* containing an update spec.

- •

  **fields**: An optional *bson\_t* containing the fields to return or **NULL**.

- •

  **\_remove**: If the matching documents should be removed.

- •

  **upsert**: If an upsert should be performed.

- •

  **\_new**: If the new version of the document should be returned.

- •

  **reply**: A maybe-**NULL** pointer to *overwritable storage* for a *bson\_t* to contain the results.

- •

  **error**: An optional location for a *bson\_error\_t* or **NULL**.

## DESCRIPTION

Update and return an object.

This is a thin wrapper around the **findAndModify** command. Either **update** or **\_remove** arguments are required.

As of MongoDB 3.2, the *mongoc\_write\_concern\_t* specified on the *mongoc\_collection\_t* will be used, if any.

**reply** is always initialized, and must be freed with *bson\_destroy()*.

On success, the output **reply** contains the full server reply to the **findAndModify** command. See the *MongoDB Manual page for findAndModify* for the expected server reply.

## ERRORS

Errors are propagated via the **error** parameter.

## RETURNS

If given invalid arguments or a server/network error occurs, returns **false** and sets **error**. Otherwise, succeeds and returns **true**. A write concern timeout or write concern error is considered a failure.

**SEE ALSO:**

```
mongoc_collection_find_and_modify_with_opts().
```

## EXAMPLE

find-and-modify.c

```
#include <mongoc/mongoc.h>
#include <stdio.h>
int
main (void)
{
   mongoc_collection_t *collection;
   mongoc_client_t *client;
   const char *uri_string = "mongodb://127.0.0.1:27017/?appname=find-and-modify-example";
   mongoc_uri_t *uri;
   bson_error_t error;
   bson_t *query;
   bson_t *update;
   bson_t reply;
   char *str;
   mongoc_init ();
   uri = mongoc_uri_new_with_error (uri_string, &error);
   if (!uri) {
      fprintf (stderr,
               "failed to parse URI: %s\n"
               "error message:       %s\n",
               uri_string,
               error.message);
      return EXIT_FAILURE;
   }
   client = mongoc_client_new_from_uri (uri);
   if (!client) {
      return EXIT_FAILURE;
   }
   mongoc_client_set_error_api (client, 2);
   collection = mongoc_client_get_collection (client, "test", "test");
   /*
    * Build our query, {"cmpxchg": 1}
    */
   query = BCON_NEW ("cmpxchg", BCON_INT32 (1));
   /*
    * Build our update. {"$set": {"cmpxchg": 2}}
    */
   update = BCON_NEW ("$set", "{", "cmpxchg", BCON_INT32 (2), "}");
   /*
    * Submit the findAndModify.
    */
   if (!mongoc_collection_find_and_modify (collection, query, NULL, update, NULL, false, false, true, &reply, &error)) {
      fprintf (stderr, "find_and_modify() failure: %s\n", error.message);
      return EXIT_FAILURE;
   }
   /*
    * Print the result as JSON.
    */
   str = bson_as_canonical_extended_json (&reply, NULL);
   printf ("%s\n", str);
   bson_free (str);
   /*
    * Cleanup.
    */
   bson_destroy (query);
   bson_destroy (update);
   bson_destroy (&reply);
   mongoc_collection_destroy (collection);
   mongoc_uri_destroy (uri);
   mongoc_client_destroy (client);
   mongoc_cleanup ();
   return EXIT_SUCCESS;
}
```

## AUTHOR

MongoDB, Inc

## COPYRIGHT

2009-present, MongoDB, Inc.