def search_and_connect(self, pvName, callback, *user_args):
"""Attempt to establish a connection to a process variable.
Parameters:
pvName: process variable name
callback: function called when connection completes and connection
status changes later on.
*user_args: user provided arguments that are passed to callback when
it is invoked.
>>> chan = CaChannel('catest')
>>> def connCB(epicsArgs, userArgs):
... if epicsArgs[1] == 6:
... print ca.name(epicsArgs[0]), "is connected"
>>> chan.search_and_connect(None, connCB, chan)
>>> status = chan.pend_event(2)
catest is connected
"""
if pvName == None:
pvName = self.pvname
else:
self.pvname = pvName
self._callbacks['connCB']=(callback, user_args)
try:
self.__chid = ca.search(pvName, self._conn_callback)
except ca.error, msg:
raise CaChannelException,msg
def search_and_connect(self, pvName, callback, *user_args):
"""Attempt to establish a connection to a process variable.
Parameters:
pvName: process variable name
callback: function called when connection completes and connection
status changes later on.
*user_args: user provided arguments that are passed to callback when
it is invoked.
>>> chan = CaChannel('catest')
>>> def connCB(epicsArgs, userArgs):
... if epicsArgs[1] == 6:
... print ca.name(epicsArgs[0]), "is connected"
>>> chan.search_and_connect(None, connCB, chan)
>>> status = chan.pend_event(2)
catest is connected
"""
if pvName == None:
pvName = self.pvname
else:
self.pvname = pvName
self._callbacks['connCB'] = (callback, user_args)
try:
self.__chid = ca.search(pvName, self._conn_callback)
except ca.error, msg:
raise CaChannelException, msg
def search(self, pvName=None):
"""Attempt to establish a connection to a process variable.
Parameters:
pvName: process variable name
>>> chan = CaChannel()
>>> chan.search('catest')
>>> status = chan.pend_io(1)
>>> chan.state()
2
"""
if pvName == None:
pvName = self.pvname
else:
self.pvname = pvName
try:
self.__chid = ca.search(pvName, None)
except ca.error, msg:
raise CaChannelException,msg
def search(self, pvName=None):
"""Attempt to establish a connection to a process variable.
Parameters:
pvName: process variable name
>>> chan = CaChannel()
>>> chan.search('catest')
>>> status = chan.pend_io(1)
>>> chan.state()
2
"""
if pvName == None:
pvName = self.pvname
else:
self.pvname = pvName
try:
self.__chid = ca.search(pvName, None)
except ca.error, msg:
raise CaChannelException, msg
def searchw(self, pvName=None):
"""Attempt to establish a connection to a process variable.
Parameters:
pvName: process variable name
>>> chan = CaChannel('non-exist-channel')
>>> chan.searchw()
Traceback (most recent call last):
...
CaChannelException: User specified timeout on IO operation expired
"""
if pvName is None:
pvName = self.pvname
else:
self.pvname = pvName
self.__chid = ca.search(pvName, None)
if self.__timeout is None:
timeout = CaChannel.ca_timeout
else:
timeout = self.__timeout
status = ca.pend_io(timeout)
if status != 0:
raise CaChannelException, ca.caError._caErrorMsg[status]
def searchw(self, pvName=None):
"""Attempt to establish a connection to a process variable.
Parameters:
pvName: process variable name
>>> chan = CaChannel('non-exist-channel')
>>> chan.searchw()
Traceback (most recent call last):
...
CaChannelException: User specified timeout on IO operation expired
"""
if pvName is None:
pvName = self.pvname
else:
self.pvname = pvName
self.__chid = ca.search(pvName, None)
if self.__timeout is None:
timeout = CaChannel.ca_timeout
else:
timeout = self.__timeout
status = ca.pend_io(timeout)
if status != 0:
raise CaChannelException, ca.caError._caErrorMsg[status]