Represents a single channel. More...

#include <client/pva/client.h>

Classes
struct	ConnectCallback
	Connection state change CB. More...

struct	GetCallback
	callback for get() and rpc() More...

struct	MonitorCallback
	Monitor event notification. More...

struct	Options
	Channel creation options. More...

struct	PutCallback
	callbacks for put() More...

Public Member Functions
	ClientChannel ()
	Construct a null channel. All methods throw. May later be assigned from a valid ClientChannel.

	ClientChannel (const std::tr1::shared_ptr< epics::pvAccess::ChannelProvider > &provider, const std::string &name, const Options &opt=Options())
	Construct a ClientChannel using epics::pvAccess::ChannelProvider::createChannel() More...

std::string	name () const
	Channel name or an empty string.

bool	valid () const

	operator bool_type () const

void	reset ()

Operation	get (GetCallback *cb, epics::pvData::PVStructure::const_shared_pointer pvRequest=epics::pvData::PVStructure::const_shared_pointer())
	Issue request to retrieve current PV value. More...

epics::pvData::PVStructure::const_shared_pointer	get (double timeout=3.0, epics::pvData::PVStructure::const_shared_pointer pvRequest=epics::pvData::PVStructure::const_shared_pointer())
	Block and retrieve current PV value. More...

Operation	rpc (GetCallback *cb, const epics::pvData::PVStructure::const_shared_pointer &arguments, epics::pvData::PVStructure::const_shared_pointer pvRequest=epics::pvData::PVStructure::const_shared_pointer())
	Start an RPC call. More...

epics::pvData::PVStructure::const_shared_pointer	rpc (double timeout, const epics::pvData::PVStructure::const_shared_pointer &arguments, epics::pvData::PVStructure::const_shared_pointer pvRequest=epics::pvData::PVStructure::const_shared_pointer())
	Block and execute remote call. More...

Operation	put (PutCallback *cb, epics::pvData::PVStructure::const_shared_pointer pvRequest=epics::pvData::PVStructure::const_shared_pointer(), bool getprevious=false)
	Initiate request to change PV. More...

detail::PutBuilder	put (const epics::pvData::PVStructure::const_shared_pointer &pvRequest=epics::pvData::PVStructure::const_shared_pointer())
	Synchronious put operation.

Monitor	monitor (MonitorCallback *cb, epics::pvData::PVStructure::const_shared_pointer pvRequest=epics::pvData::PVStructure::const_shared_pointer())
	Begin subscription. More...

MonitorSync	monitor (const epics::pvData::PVStructure::const_shared_pointer &pvRequest=epics::pvData::PVStructure::const_shared_pointer(), epicsEvent *event=0)
	Begin subscription w/o callbacks. More...

Operation	info (InfoCallback *cb, const std::string &subfld=std::string())
	Request PV type info. More...

epics::pvData::FieldConstPtr	info (double timeout=3.0, const std::string &subfld=std::string())
	Synchronious getField opreation.

void	addConnectListener (ConnectCallback *)
	Append to list of listeners. More...

void	removeConnectListener (ConnectCallback *)
	Remove from list of listeners.

void	show (std::ostream &strm) const

Friends
class	ClientProvider

void	detail::registerRefTrack ()

friend::std::ostream &	operator<< (::std::ostream &strm, const ClientChannel &op)

Detailed Description

Represents a single channel.

This class has two sets of methods, those which block for completion, and those which use callbacks to signal completion.

Those which block accept a 'timeout' argument (in seconds).

Those which use callbacks accept a 'cb' argument and return an Operation or Monitor handle object.

Definition at line 266 of file client.h.

Constructor & Destructor Documentation

pvac::ClientChannel::ClientChannel	(	const std::tr1::shared_ptr< epics::pvAccess::ChannelProvider > &	provider,
		const std::string &	name,
		const Options &	opt = `Options()`
	)

Construct a ClientChannel using epics::pvAccess::ChannelProvider::createChannel()

Does not block.

Exceptions

std::logic_error	if the provider is NULL or name is an empty string
std::runtime_error	if the ChannelProvider can't provide

Member Function Documentation

void pvac::ClientChannel::addConnectListener ( ConnectCallback * )

Append to list of listeners.

Parameters

cb	Channel dis/connect notification callback. Must outlive ClientChannel or call to removeConnectListener()

Operation pvac::ClientChannel::get	(	GetCallback *	cb,
		epics::pvData::PVStructure::const_shared_pointer	pvRequest = `epics::pvData::PVStructure::const_shared_pointer()`
	)

Issue request to retrieve current PV value.

Parameters

cb	Completion notification callback. Must outlive Operation (call Operation::cancel() to force release)
pvRequest	if NULL defaults to "field()".

epics::pvData::PVStructure::const_shared_pointer pvac::ClientChannel::get	(	double	timeout = `3.0`,
		epics::pvData::PVStructure::const_shared_pointer	pvRequest = `epics::pvData::PVStructure::const_shared_pointer()`
	)

Block and retrieve current PV value.

Parameters

timeout	in seconds
pvRequest	if NULL defaults to "field()".

Exceptions

Timeout or std::runtime_error

Operation pvac::ClientChannel::info	(	InfoCallback *	cb,
		const std::string &	subfld = `std::string()`
	)

Request PV type info.

Note: This type may not be the same as the types used in the get/put/monitor operations.

Monitor pvac::ClientChannel::monitor	(	MonitorCallback *	cb,
		epics::pvData::PVStructure::const_shared_pointer	pvRequest = `epics::pvData::PVStructure::const_shared_pointer()`
	)

Begin subscription.

Parameters

cb	Completion notification callback. Must outlive Monitor (call Monitor::cancel() to force release)

MonitorSync pvac::ClientChannel::monitor	(	const epics::pvData::PVStructure::const_shared_pointer &	pvRequest = `epics::pvData::PVStructure::const_shared_pointer()`,
		epicsEvent *	event = `0`
	)

Begin subscription w/o callbacks.

Parameters

event If not NULL, then subscription events are signaled to this epicsEvent. Use MonitorSync::test() to see if a subscription has an event waiting. Otherwise an internal epicsEvent is allocated for use with MonitorSync::wait()

Note: For simple usage with a single MonitorSync, pass event=NULL and call MonitorSync::wait(). If more than one MonitorSync is being created, then pass a custom epicsEvent and use MonitorSync::test() to find which subscriptions have events pending.

Operation pvac::ClientChannel::put	(	PutCallback *	cb,
		epics::pvData::PVStructure::const_shared_pointer	pvRequest = `epics::pvData::PVStructure::const_shared_pointer()`,
		bool	getprevious = `false`
	)

Initiate request to change PV.

Parameters

cb	Completion notification callback. Must outlive Operation (call Operation::cancel() to force release)
pvRequest	if NULL defaults to "field()".
getprevious	If true, fetch a previous value of the PV and make this available as PutCallback::Args::previous and previousmask. If false, then previous=NULL

Operation pvac::ClientChannel::rpc	(	GetCallback *	cb,
		const epics::pvData::PVStructure::const_shared_pointer &	arguments,
		epics::pvData::PVStructure::const_shared_pointer	pvRequest = `epics::pvData::PVStructure::const_shared_pointer()`
	)

Start an RPC call.

Parameters

cb	Completion notification callback. Must outlive Operation (call Operation::cancel() to force release)
arguments	encoded call arguments
pvRequest	if NULL defaults to "field()".

epics::pvData::PVStructure::const_shared_pointer pvac::ClientChannel::rpc	(	double	timeout,
		const epics::pvData::PVStructure::const_shared_pointer &	arguments,
		epics::pvData::PVStructure::const_shared_pointer	pvRequest = `epics::pvData::PVStructure::const_shared_pointer()`
	)

Block and execute remote call.

Parameters

timeout	in seconds
arguments	encoded call arguments
pvRequest	if NULL defaults to "field()".

The documentation for this class was generated from the following file:

client/pva/client.h

Classes

Public Member Functions

Friends

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation