From d3a298cd7c0381c682a09e5eef4544a2b3bf8612 Mon Sep 17 00:00:00 2001
From: Michael Davidsaver <mdavidsaver@bnl.gov>
Date: Sat, 30 Mar 2013 15:03:11 -0400
Subject: [PATCH] add async example

---
 test.cmd         |  4 +++
 testApp/test1.db | 10 ++++++++
 testApp/test2.py | 65 ++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 79 insertions(+)
 create mode 100644 testApp/test2.py

diff --git a/test.cmd b/test.cmd
index e1b83f5..08ec763 100644
--- a/test.cmd
+++ b/test.cmd
@@ -8,6 +8,10 @@ devsup_registerRecordDeviceDriver(pdbbase)
 #evalPy "import devsup.hooks"
 #evalPy "devsup.hooks.debugHooks()"
 
+evalPy "import test2"
+evalPy "test2.addDrv('AAAA')"
+evalPy "test2.addDrv('BBBB')"
+
 dbLoadRecords("db/test1.db","P=md:")
 
 iocInit()
diff --git a/testApp/test1.db b/testApp/test1.db
index 66cce41..ecb729d 100644
--- a/testApp/test1.db
+++ b/testApp/test1.db
@@ -4,3 +4,13 @@ record(longin, "$(P)li:cnt") {
   field(INP , "@test1 hello world")
   field(SCAN, "1 second")
 }
+
+record(longin, "$(P)val:a") {
+  field(DTYP, "Python Device")
+  field(INP , "@test2 AAAA")
+}
+
+record(longin, "$(P)val:b") {
+  field(DTYP, "Python Device")
+  field(INP , "@test2 AAAA")
+}
diff --git a/testApp/test2.py b/testApp/test2.py
new file mode 100644
index 0000000..09b5a43
--- /dev/null
+++ b/testApp/test2.py
@@ -0,0 +1,65 @@
+
+import threading, time
+from devsup.hooks import addHook
+
+insts = {}
+
+class Driver(threading.Thread):
+    def __init__(self, name):
+        super(Driver,self).__init__()
+        self.name = name
+        self._lock = threading.Lock()
+        self._recs = set()
+        self._run = True
+        self._stop = threading.Event()
+        self.value = 0
+        addHook('AfterIocRunning', self.start)
+        addHook('AtIocExit', self.stop)
+
+    def stop(self):
+        print 'Stopping driver',self.name
+        with self._lock:
+            self._run = False
+        self._stop.wait()
+        print 'Finished with',self.value
+
+    def addrec(self, rec):
+        with self._lock:
+            self._recs.add(rec)
+    def delrec(self, rec):
+        with self._lock:
+            self._recs.remove(rec)
+
+    def run(self):
+        try:
+            while self._run:
+                time.sleep(1.0)
+                with self._lock:
+                    val = self.value
+                    self.value += 1
+                    for R in self._recs:
+                        R.record.scan(sync=True, reason=val)
+        finally:
+            self._stop.set()
+
+def addDrv(name):
+    print 'Create driver',name
+    insts[name] = Driver(name)
+
+class Device(object):
+    def __init__(self, rec, drv):
+        self.driver, self.record = drv, rec
+        self.driver.addrec(self)
+        self.val = rec.field('VAL')
+    def detach(self, rec):
+        self.driver.delrec(self)
+    def process(self, rec, data):
+        if data is None:
+            print rec,'Someone processed me?'
+        else:
+            print rec,'update to',data
+            self.val.putval(data)
+
+def build(rec, args):
+    drv = insts[args]
+    return Device(rec, drv)