HP-UX

NAME

viUninstallHandler − Allows application to uninstall handlers

SYNOPSIS

viUninstallHandler(ViSession vi, ViEventType eventType,
ViHndlr handler, ViAddr userHandle);

Description

 
This function allows applications to uninstall handlers for events on sessions.  Applications should also specify the value in the userHandle parameter that was passed to viInstallHandler while installing the handler.  VTL identifies handlers uniquely using the handler reference and this value.  All the handlers, for which the handler reference and the value matches, are uninstalled.
 

Parameters

vi An input parameter.  Unique logical identifier to a session. 
 

eventType An input parameter.  Logical event identifier. 
 

handler An input parameter.  Interpreted as a valid reference to a handler to be installed by an application. (See the following table.) 
 

userHandle An input parameter.  A value specified by an application that can be used for identifying handlers uniquely in a session for an event. 
 
 

The following events can be enabled:

VI_EVENT_SERVICE_REQ Notification that a device is requesting service. 
 

VI_EVENT_VXI_SIGP Notification that a VXI signal or VXI interrupt has been received from a device. 
 

VI_EVENT_TRIG Notification that a hardware trigger was received from a device. 
 
 
 

Special Values for handler Parameter:

VI_ANY_HNDLR Uninstall all the handlers with the matching value in the handler parameter. 
 
 

Return Values

 
This is the functional return status.  It returns either a completion code or an error code as follows.
 

VI_SUCCESS Event handler successfully uninstalled. 
 
 

VI_ERROR_INV_SESSION VI_ERROR_INV_OBJECT The given session or object reference is invalid (both are the same value). 
 

VI_ERROR_INV_EVENT Specified event type is not supported by the resource. 
 

VI_ERROR_INV_HNDLR_REF Either the specified handler reference or the user context value (or both) does not match any installed handler. 
 

See Also

 
See the handler prototype, viEventHandler, for its parameter description.  Also refer to the viEnableEvent description for information about enabling different event handling mechanisms.  Refer to individual event descriptions for context definitions.
 

AUTHOR

viUninstallHandler was developed by HP
 

Hewlett-Packard Comapny  —  September 29, 1999