# PR_ExitMonitor

Decrements the entry count associated with a specified monitor and, if
the entry count reaches zero, releases the monitor's lock.

## Syntax

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

PRStatus PR_ExitMonitor(PRMonitor *mon);
```

### Parameter

The function has the following parameter:

`mon`

: A reference to an existing structure of type {ref}`PRMonitor`. The
  monitor object referenced must be one for which the calling thread
  currently holds the lock.

### Returns

The function returns one of the following values:

- If successful, `PR_SUCCESS`.
- If unsuccessful (the calling thread has not entered the monitor),
  `PR_FAILURE`.

## Description

If the decremented entry count is zero, {ref}`PR_ExitMonitor` releases the
monitor's lock. Threads that were blocked trying to enter the monitor
will be rescheduled.