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