Extra File Descriptors

Functions
int	GetExtraFD (void *extra_data, struct IoExpandStruct *pFuncs)
	Returns a file descriptor for the structure passed as the IoExpandStruct. FreeExtraFd( ) will release the fd back to the pool of available fds.
void *	GetExtraData (int fd)
	Returns the extra structure value from IoExpandStruct associated with the file descriptor.
void	FreeExtraFd (int fd)
	Free a file descriptor and associated resources.
int	GetFreeExtraFDCount ()
	Returns the number of free file descriptors.
int	GetFreeSocketCount (void)
	Returns the number of free sockets.

Detailed Description

#include< iointernal.h >

The NetBurner environment integrates the RTOS, TCP/IP stack, and other peripherals with a file I/O system based on file descriptors. A file descriptor can be described as a handle to a network socket, serial port, system peripheral, or any other object that can be read or written to. Most of the API functions pass a file descriptor as a parameter to such an object. These function are available if you wish to use the file descritpor system capabilities for your own application purposes. Please refer to the File Descriptor section in the Programmers Guide.

Function Documentation

FreeExtraFd()

void FreeExtraFd

(

int

fd

)

#include <iointernal.h>

Free a file descriptor and associated resources.

Parameters

fd	File descriptor

GetExtraData()

void * GetExtraData

(

int

fd

)

#include <iointernal.h>

Returns the extra structure value from IoExpandStruct associated with the file descriptor.

Parameters

fd	File descriptor

Return values

Value

of the extra member of the structure

GetExtraFD()

int GetExtraFD	(	void *	extra_data,
		struct IoExpandStruct *	pFuncs )

#include <iointernal.h>

Returns a file descriptor for the structure passed as the IoExpandStruct. FreeExtraFd( ) will release the fd back to the pool of available fds.

Parameters

extra_data	The optional extra_data void pointer can be used to pass data into the file descriptor
*pFuncs	Structure containing callback functions for such things as read, write, close, and the extra_data variable

Return values

Value	greater than 0, representing the file descriptor on success
-1	on failure

GetFreeExtraFDCount()

int GetFreeExtraFDCount

(

)

#include <iointernal.h>

Returns the number of free file descriptors.

Return values

Number

of free extra file descriptors

GetFreeSocketCount()

int GetFreeSocketCount

(

void

)

#include <iointernal.h>

Returns the number of free sockets.

Return values

Number

of free sockets