HP UX 11i v1 I/O Cards manual Zluopen

ZCOM C I/F Library Routines

ZLUOPEN (3X)

		ZLUOPEN (3X)
NAME		zluopen – Open a ZLU file
SYNOPSIS
#include	<zcom/zcomsys.h>
#include	<zcom/zcomcall.h> /* if compiled with ANSI C (recommended) */
int zluopen (zap, mode, fd)
zaddr_type		*zap;
int		mode;
int		*fd;
DESCRIPTION		Routine zluopen opens the device file associated with a program ZLU for
		use with the standard HP-UX file access routines. The zap parameter
		points to the program ZLU to be accessed. If successful, a file descriptor
		for the opened program ZLU device file is returned through the fd
		pointer. The mode parameter is intended for a future enhancement and
		is not used at this time. For future compatibility, mode should be set to
		zero.

The zluopen routine only allows opening the device files for the range of program ZLUs in the local system. If zap specifies a terminal ZLU, or a ZLU on remote node, the request will also be rejected with an error.

In the current implementation of ZCOM, only the select and close functions are allowed on the returned file descriptor. Other operations (such as read and write) will result in error ENOSYS (Function is not available). A select for read on the returned file descriptor is to check whether input data is available on a program ZLU. A select on write on the returned file descriptor will always return TRUE, while a select on exception always returns FALSE.

The libraries libzcom_c.a and libpthread.a must be linked into the calling program by giving the options “-lzcom_c -lpthread” to cc(1) or ld(1).

240 Chapter 4