NAME

hpib_status_wait() − wait until the requested status condition becomes true

SYNOPSIS

#include <dvio.h>

int hpib_status_wait(int eid, int status); #include <dvio.h>

DESCRIPTION

hpib_status_wait() waits until a specific condition has occurred before returning.  eid is an entity identifier of an open HP-IB raw bus device file obtained from an open(), dup(), fcntl(), or creat() call.  status is an integer specifying what information is returned.  The possible values for status and their associated meanings are:

WAIT_FOR_SRQ Wait until SRQ line is enabled. 

WAIT_FOR_CONTROL Wait until this channel is active controller. 

WAIT_FOR_TALKER Wait until this channel is addressed as talker. 

WAIT_FOR_LISTENER Wait until this channel is addressed as listener. 

The wait is subject to the current timeout in effect.  If a timeout occurs before the desired condition occurs, the function returns with an error. 

RETURN VALUE

hpib_status_wait() returns zero when the condition requested becomes true.  A value of −1 is returned if an error occurs.  A −1 is also returned if a timeout occurs before the desired condition becomes true. 

ERRORS

hpib_status_wait() fails under the following circumstances, and sets errno (see errno(2)) to the value in square brackets:

[EBADF] eid does not refer to an open file. 

[ENOTTY] eid does not refer to an HP-IB raw bus device file. 

[ETIMEDOUT] a timeout occurred. 

[EINVAL] status contains an invalid value. 

[EACCES] the interface associated with this eid is locked by another process and O_NDELAY is set for this eid (see io_lock(3I)). 

DEPENDENCIES

Series 300/400:

EIO is returned if a timeout occurs. 

The following error is also defined:

[EIO] the device is active controller and status specifies WAIT_FOR_TALKER or WAIT_FOR_LISTENER. 

AUTHOR

hpib_status_wait() was developed by HP. 

Hewlett-Packard Company  —  HP-UX Release 9.0: August 1992