def get(self, name, request=None, timeout=5.0, throw=True):
"""Fetch current value of some number of PVs.
:param name: A single name string or list of name strings
:param request: A :py:class:`p4p.Value` or string to qualify this request, or None to use a default.
:param float timeout: Operation timeout in seconds
:param bool throw: When true, operation error throws an exception. If False then the Exception is returned instead of the Value
:returns: A p4p.Value or Exception, or list of same. Subject to :py:ref:`unwrap`.
When invoked with a single name then returns is a single value.
When invoked with a list of name, then returns a list of values
>>> ctxt = Context('pva')
>>> V = ctxt.get('pv:name')
>>> A, B = ctxt.get(['pv:1', 'pv:2'])
>>>
"""
singlepv = isinstance(name, (bytes, unicode))
if singlepv:
return self._get_one(name, request=request, timeout=timeout, throw=throw)
elif request is None:
request = [None] * len(name)
assert len(name) == len(request), (name, request)
return cothread.WaitForAll(
[cothread.Spawn(self._get_one, N, request=R, timeout=timeout, throw=throw,
raise_on_wait=True)
for N, R in zip(name, request)]
)
def fill_buffer_array(pvs, length, **kargs):
return cothread.WaitForAll([
cothread.Spawn(fill_buffer_one,
pv,
length,
raise_on_wait=True,
**kargs) for pv in pvs
])
def put(self, name, values, request=None, process=None, wait=None, timeout=5.0, get=True, throw=True):
"""Write a new value of some number of PVs.
:param name: A single name string or list of name strings
:param values: A single value, a list of values, a dict, a `Value`. May be modified by the constructor nt= argument.
:param request: A :py:class:`p4p.Value` or string to qualify this request, or None to use a default.
:param float timeout: Operation timeout in seconds
:param bool throw: When true, operation error throws an exception.
If False then the Exception is returned instead of the Value
:param str process: Control remote processing. May be 'true', 'false', 'passive', or None.
:param bool wait: Wait for all server processing to complete.
:param bool get: Whether to do a Get before the Put. If True then the value passed to the builder callable
will be initialized with recent PV values. eg. use this with NTEnum to find the enumeration list.
:returns: A None or Exception, or list of same
When invoked with a single name then returns is a single value.
When invoked with a list of name, then returns a list of values
If 'wait' or 'process' is specified, then 'request' must be omitted or None.
>>> ctxt = Context('pva')
>>> ctxt.put('pv:name', 5.0)
>>> ctxt.put(['pv:1', 'pv:2'], [1.0, 2.0])
>>> ctxt.put('pv:name', {'value':5})
>>>
The provided value(s) will be automatically coerced to the target type.
If this is not possible then an Exception is raised/returned.
Unless the provided value is a dict, it is assumed to be a plain value
and an attempt is made to store it in '.value' field.
"""
if request and (process or wait is not None):
raise ValueError("request= is mutually exclusive to process= or wait=")
elif process or wait is not None:
request = 'field()record[block=%s,process=%s]' % ('true' if wait else 'false', process or 'passive')
singlepv = isinstance(name, (bytes, unicode))
if singlepv:
return self._put_one(name, values, request=request, timeout=timeout, throw=throw, get=get)
elif request is None:
request = [None] * len(name)
assert len(name) == len(request), (name, request)
assert len(name) == len(values), (name, values)
return cothread.WaitForAll(
[cothread.Spawn(self._put_one, N, V, request=R, timeout=timeout, throw=throw, get=get,
raise_on_wait=True)
for N, V, R in zip(name, values, request)]
)