# PR_CreatePipe

Creates an anonymous pipe and retrieves file descriptors for the read
and write ends of the pipe.

## Syntax

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

PRStatus PR_CreatePipe(
  PRFileDesc **readPipe,
  PRFileDesc **writePipe);
```

### Parameters

The function has the following parameters:

`readPipe`

: A pointer to a {ref}`PRFileDesc` pointer. On return, this parameter
  contains the file descriptor for the read end of the pipe.

`writePipe`

: A pointer to a {ref}`PRFileDesc` pointer. On return, this parameter
  contains the file descriptor for the write end of the pipe.

### Returns

The function returns one of these values:

- If the pipe is successfully created, `PR_SUCCESS`.
- If the pipe is not successfully created, `PR_FAILURE`. The error
  code can be retrieved via {ref}`PR_GetError`.

## Description

{ref}`PR_CreatePipe` creates an anonymous pipe. Data written into the write
end of the pipe can be read from the read end of the pipe. Pipes are
useful for interprocess communication between a parent and a child
process. When the pipe is no longer needed, both ends should be closed
with calls to {ref}`PR_Close`.

{ref}`PR_CreatePipe` is currently implemented on Unix, Linux, Mac OS X, and
Win32 only.