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

# bson\_append\_null(3)

## SYNOPSIS

```
#define BSON_APPEND_NULL(b, key) bson_append_null (b, key, (int) strlen (key))
bool
bson_append_null (bson_t *bson, const char *key, int key_length);
```

## PARAMETERS

- •

  **bson**: A *bson\_t*.

- •

  **key**: An ASCII C string containing the name of the field.

- •

  **key\_length**: The length of **key** in bytes, or -1 to determine the length with **strlen()**.

## DESCRIPTION

The *bson\_append\_null()* function shall append a new element to **bson** of type BSON\_TYPE\_NULL.

## RETURNS

Returns **true** if the operation was applied successfully. The function will fail if appending the value grows **bson** larger than INT32\_MAX.

## AUTHOR

MongoDB, Inc

## COPYRIGHT

2009-present, MongoDB, Inc.