lp(7D)								      Devices								    lp(7D)

NAME

       lp - driver for parallel port

SYNOPSIS

       include <sys/bpp_io.h>
       fd = open("/dev/lpn", flags);

DESCRIPTION

       The  lp	driver	provides  the  interface  to  the parallel ports used by printers for x86 based systems. The lp driver is implemented as a
       STREAMS device.

IOCTLS

       BPPIOC_TESTIO	       Test transfer readiness. This command checks to see if a read or write transfer would succeed based on pin  status.
			       If  a  transfer would succeed,  0 is returned. If a transfer would fail,  -1 is returned, and errno is set to  EIO.
			       The error status can be retrieved using the  BPPIOC_GETERR ioctl() call.

       BPPIOC_GETERR	       Get last error status. The argument is a pointer to a  struct bpp_error_status. See below for a description of  the
			       elements  of  this structure. This structure indicates the status of all the appropriate status bits at the time of
			       the most recent error condition during a  read(2) or write(2) call, or the status of the bits at  the  most  recent
			       BPPIOC_TESTIO ioctl(2) call. The application can check transfer readiness without attempting another transfer using
			       the  BPPIOC_TESTIO ioctl().

   Error Pins Structure
       This structure and symbols are defined in the include file <sys/bpp_io.h>:

       struct bpp_error_status {
	       char  timeout_occurred;	 /* Not use */
	    char  bus_error;	      /* Not use */
	    uchar_t pin_status;       /* Status of pins which could cause an error */
       };

       /* Values for pin_status field */
       #define BPP_ERR_ERR 0x01   /* Error pin active */
       #define BPP_SLCT_ERR 0x02  /* Select pin active */
       #define BPP_PE_ERR 0x04	  /* Paper empty pin active */

       Note: Other pin statuses are defined in	<sys/bpp_io.h>, but BPP_ERR_ERR, BPP_SLCT_ERR and BPP_PE_ERR are the only ones valid for  the  x86
       lp driver.

ERRORS

       EIO	       A  BPPIOC_TESTIO  ioctl()  call	is  attempted while a condition exists that would prevent a transfer (such as a peripheral
		       error).

       EINVAL	       An ioctl() is attempted with an invalid value in the command argument.

FILES

       /platform/i86pc/kernel/drv/lp.conf      configuration file for  lp driver

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Architecture		     |x86			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       sysbus(4), attributes(5), streamio(7I)

NOTES

       A read operation on a bi-directional parallel port is not supported.

SunOS 5.10							    21 May 1997 							    lp(7D)