42 lines
1021 B
Markdown
42 lines
1021 B
Markdown
# PR_Available
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Determines the number of bytes (expressed as a 32-bit integer) that are
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available for reading beyond the current read-write pointer in a
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specified file or socket.
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## Syntax
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```{code}
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#include <prio.h>
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PRInt32 PR_Available(PRFileDesc *fd);
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```
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### Parameter
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The function has the following parameter:
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`fd`
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: Pointer to a {ref}`PRFileDesc` object representing a file or socket.
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### Returns
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The function returns one of the following values:
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- If the function completes successfully, it returns the number of
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bytes that are available for reading. For a normal file, these are
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the bytes beyond the current file pointer.
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- If the function fails, it returns the value -1. The error code can
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then be retrieved via {ref}`PR_GetError`.
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## Description
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{ref}`PR_Available` works on normal files and sockets. {ref}`PR_Available`
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does not work with pipes on Win32 platforms.
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## See Also
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If the number of bytes available for reading is out of the range of a
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32-bit integer, use {ref}`PR_Available64`.
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