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