hpib_bus_status(3I)

DESCRIPTION

hpib_bus_status() obtains status information about an HP-IB channel. 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 determining what status information is returned for a particular call. The values defined for status and their associated meanings are:

The remote-state status is not defined when the interface is the active controller, although reading remote-state status in such a situation is not an error. Determining the status of the NDAC line is not available on all machines, and its use is therefore discouraged to ensure compatibility among various systems. Machines that do not support sensing the NDAC line return an error.

RETURN VALUE

The value returned by hpib_bus_status() depends upon the value of status. If status is CURRENT_BUS_ADDRESS, the return value is either the HP-IB bus address or -1 if an error occurred. If status is any of the other values, the return value is 0 if the condition is false (the line is clear), 1 if the condition is true (the line is set), or -1 if an error occurred.

ERRORS

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

AUTHOR

hpib_bus_status() was developed by HP.