IEEE1284_OPEN(3)						     Functions							  IEEE1284_OPEN(3)

NAME

       ieee1284_open - open a port

SYNOPSIS

       #include <ieee1284.h>

       int ieee1284_open(struct parport *port, int flags, int *capabilities);

DESCRIPTION

       In order to begin using a port it must be opened. Any initial set-up of the port is done at this stage. When an open port is no longer
       needed it should be closed with ieee1284_close(3).

       The possible flags are:

       F1284_EXCL
	   This device cannot share the port with any other device. If this is the case it must be declared at this stage, so that other drivers
	   trying to access the port know not to bother; otherwise they will wait until this driver releases the port, i.e. never.

	   The iopl/dev-port access methods don't support this yet, but the ppdev ones do.

       If capabilities is not NULL it must point to storage for an int, which will be treated as a set of flags, one per bit, which the library
       sets or clears as appropriate. If a capability is present it will be used when asked for. They are:

       CAP1284_RAW
	   Pin-level access is available. If this capability is present then the following functions are effective: ieee1284_write_data,
	   ieee1284_read_status, ieee1284_wait_status, ieee1284_write_control, ieee1284_read_control, ieee1284_frob_control.

       CAP1284_NIBBLE
	   There is an implementation of nibble mode for this port.

       CAP1284_BYTE
	   There is an implementation of byte mode for this port.

       CAP1284_COMPAT
	   There is an implementation of compatibility mode for this port.

       CAP1284_ECP
	   There is a hardware implementation of ECP mode for this port.

       CAP1284_ECPRLE
	   There is an RLE-aware implementation of ECP mode for this port (the F1284_RLE flag is recognised by the ECP transfer functions).

       CAP1284_ECPSWE
	   There is a software implementation of ECP mode for this port.

       CAP1284_BECP
	   There is an implementation of bounded ECP mode for this port.

       CAP1284_EPP
	   There is a hardware implementation of EPP mode for this port.

       CAP1284_EPPSWE
	   There is a software implementation of EPP mode for this port.

       CAP1284_IRQ
	   An interrupt line is configured for this port and interrupt notifications can be received using ieee1284_get_irq_fd(3).

       CAP1284_DMA
	   A DMA channel is configured for this port.

RETURN VALUE

       E1284_OK
	   The port is now opened.

       E1284_INIT
	   There was a problem during port initialization. This could be because another driver has opened the port exclusively, or some other
	   reason.

       E1284_NOMEM
	   There is not enough memory.

       E1284_NOTAVAIL
	   One or more of the supplied flags is not supported by this type of port.

       E1284_INVALIDPORT
	   The port parameter is invalid (for instance, the port may already be open).

       E1284_SYS
	   There was a problem at the operating system level. The global variable errno has been set appropriately.

SEE ALSO

       ieee1284_close(3)

AUTHOR

       Tim Waugh <twaugh@redhat.com>
	   Author.

COPYRIGHT

       Copyright (C) 2001-2003 Tim Waugh

								    09/18/2007							  IEEE1284_OPEN(3)