RxUsbRegisterChangeNotification
Description
Registers semaphores for generic attach/detach notification of USB devices.
Syntax
rc = RxUsbRegisterChangeNotification(NotifyID,hDevAdd,hDevRem)
Parameters
- NotifyID
- the name of the variable to receive the Notification Identifier.
- hDevAdd
- the handle of the event semaphore to be posted on device attach.
- hDevRem
- the handle of the event semaphore to be posted on device detach.
Return Code
Errors
Remarks
Example Code
/* add SysCreateEventSem */
rc = RxFuncAdd('SysCreateEventSem','RexxUtil','SysCreateEventSem')
say '+SysCreateEventSem(),RC=0x'd2x(rc)
/* invoke SysCreateEventSem() */
hSemAttach = SysCreateEventSem()
say '*SysCreateEventSem(),RC=0x'd2x(rc)
hSemDetach = SysCreateEventSem()
say '*SysCreateEventSem(),RC=0x'd2x(rc)
/* drop SysCreateEventSem */
rc = RxFuncDrop('SysCreateEventSem')
say '-SysCreateEventSem(),RC=0x'd2x(rc)
/* add RxUsbRegisterChangeNotification */
rc = RxFuncAdd('RxUsbRegisterChangeNotification','usbcalls','RxUsbRegisterChangeNotification')
say '+RxUsbRegisterChangeNotification(),RC=0x'd2x(rc)
/* invoke RxUsbRegisterChangeNotification */
hDevAdd = hSemAttach; /* attach semaphore handle */
hDevRem = hSemDetach; /* detach semaphore handle */
drop NotifyID /* to receive the notification identifier */
rc = RxUsbRegisterChangeNotification(NotifyID,hDevAdd,hDevRem)
say '*RxUsbRegisterChangeNotification(),RC=0x'd2x(rc)
/* drop RxUsbRegisterChangeNotification */
rc = RxFuncDrop('RxUsbRegisterChangeNotification')
say '-RxUsbRegisterChangeNotification(),RC=0x'd2x(rc)
/* add SysWaitEventSem */
rc = RxFuncAdd('SysWaitEventSem','RexxUtil','SysWaitEventSem')
say '+SysWaitEventSem(),RC=0x'd2x(rc)
/* invoke SysWaitEventSem() */
timeout = 8000; /* await 8 seconds */
rc = SysWaitEventSem(hSemAttach,timeout)
say '*SysWaitEventSem(),RC=0x'd2x(rc)
if (rc=0) then say 'obtained Attach Notification'
rc = SysWaitEventSem(hSemDetach,timeout)
say '*SysWaitEventSem(),RC=0x'd2x(rc)
if (rc=0) then say 'obtained Detach Notification'
/* drop SysWaitEventSem */
rc = RxFuncDrop('SysWaitEventSem')
say '-SysWaitEventSem(),RC=0x'd2x(rc)