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# PR_RecvFrom
Receives bytes from a socket and stores the sending peer's address.
## Syntax
```{code}
#include <prio.h>
PRInt32 PR_RecvFrom(
PRFileDesc *fd,
void *buf,
PRInt32 amount,
PRIntn flags,
PRNetAddr *addr,
PRIntervalTime timeout);
```
### Parameters
The function has the following parameters:
`fd`
: A pointer to a {ref}`PRFileDesc` object representing a socket.
`buf`
: A pointer to a buffer containing the data received.
`amount`
: The size of `buf` (in bytes).
`flags`
: This obsolete parameter must always be zero.
`addr`
: A pointer to the {ref}`PRNetAddr` object that will be filled in with the
address of the sending peer on return.
`timeout`
: A value of type {ref}`PRIntervalTime` specifying the time limit for
completion of the receive operation.
### Returns
The function returns one of the following values:
- A positive number indicates the number of bytes actually received.
- The value 0 means the network connection is closed.
- The value -1 indicates a failure. The reason for the failure can be
obtained by calling {ref}`PR_GetError`.
## Description
{ref}`PR_RecvFrom` receives up to a specified number of bytes from socket,
which may or may not be connected. The operation blocks until one or
more bytes are transferred, a timeout has occurred, or there is an
error. No more than `amount` bytes will be transferred.
{ref}`PR_RecvFrom` is usually used with a UDP socket.