# PR_GetIdentitiesLayer

Finds the layer with the specified identity in the specified stack of
layers.

## Syntax

```{code}
#include <prio.h>

PRFileDesc* PR_GetIdentitiesLayer(
  PRFileDesc* stack,
  PRDescIdentity id);
```

### Parameters

The function has the following parameters:

`stack`

: A pointer to a {ref}`PRFileDesc` object that is a layer in a stack of
  layers.

`id`

: The identity of the specified layer.

### Returns

The function returns one of the following values:

- If successful, a pointer to a file descriptor of the layer with the
  specified identity in the given stack of layers.
- If not successful, `NULL`.

## Description

The stack of layers to be searched is specified by the fd parameter,
which is a layer in the stack. Both the layers underneath fd and the
layers above fd are searched to find the layer with the specified
identity.