Exception in p4p

[Torsten Bögershausen via Core-talk <core-talk at aps.anl.gov>]

Hej All,

I am seeing some unexpected exceptions when running
tests via pytest and p4p.

After a lot of digging, the exception problem could be
cooked down into 2 test cases,
reading the .RBV and the .CNEN field of a motorRecord,
before closing the connection:

class Test(unittest.TestCase):
    url_string = os.getenv("TESTEDMOTORAXIS")
    print(f"url_string={url_string}")

    axisTestUtil = AxisTestUtil(url_string, log_debug=True)
    axisComm = axisTestUtil.getAxis()

    # Read variables (floating point)
    def test_TC_01101(self):
        tc_no = "01101"
        rbv = float(self.axisComm.getActPos(tc_no=tc_no))
        print(
            f"{datetime.datetime.now():%Y-%m-%d %H:%M:%S} 
{filnam}:{lineno()} {tc_no} rbv={rbv}"
        )

    # Read variables (boolean)
    def test_TC_01102(self):
        tc_no = "01102"
        enabled = self.axisComm.getEnabledStatus(tc_no=tc_no)
        print(
            f"{datetime.datetime.now():%Y-%m-%d %H:%M:%S} 
{filnam}:{lineno()} {tc_no} enabled={enabled}"
        )

    def teardown_class(self):
        tc_no = "011999"
        print(
            f"{datetime.datetime.now():%Y-%m-%d %H:%M:%S} 
{filnam}:{lineno()} {tc_no} teardown_class"
        )
        self.axisTestUtil.close()


The somewhat shortened log seems to indicate that the exception happens
before the shutdown.
And the problem is the both under MacOs with python3.9 and
Debian with python3.7



platform linux -- Python 3.7.3, pytest-7.2.0, pluggy-1.0.0
collecting ... url_string=pva://IOC:m1
collected 2 items 


Does anybody have a clue or hint ?
Thanks
/Torsten

011_Basic_Communication.py 2022-12-14 13:14:03 ConnP4P get IOC:m1.RBV
2022-12-14 13:14:03 ConnP4P get IOC:m1.RBV ret=Wed Dec 14 13:10:50 2022 
100.11 time=0.01
2022-12-14 13:14:03 011:39 01101 rbv=100.11
.2022-12-14 13:14:03 ConnP4P get IOC:m1.CNEN
2022-12-14T13:14:03.905922950 CRIT pvxs.tcp.io Server Error while 
processing cmd 0x0a: vector::_M_range_check
Dumping a stack trace of thread 'PVXCTCP':
[    0x7f4fc8afeb6b]: 
...python3.7/site-packages/p4p/../epicscorelibs/lib/libCom.so.7.0.7.99.0(epicsStackTrace+0x4b)
[    0x7f4fc8deb4b5]: 
...python3.7/site-packages/p4p/../pvxslibs/lib/libpvxs.so.1.1(_ZN4pvxs6detail11_log_printfEjPKcz+0xa5)
[    0x7f4fc8dadcf6]: 
...python3.7/site-packages/p4p/../pvxslibs/lib/libpvxs.so.1.1(_ZN4pvxs4impl8ConnBase7bevReadEv+0x696)
[    0x7f4fc8dae031]: 
...python3.7/site-packages/p4p/../pvxslibs/lib/libpvxs.so.1.1(_ZN4pvxs4impl8ConnBase8bevReadSEP11buffereventPv+0x21)
[    0x7f4fc871e432]: 
...python3.7/site-packages/p4p/../pvxslibs/lib/./libevent_core.so.2.2.0(bufferevent_run_deferred_callbacks_locked+0x82)
[    0x7f4fc8717db6]: 
...python3.7/site-packages/p4p/../pvxslibs/lib/./libevent_core.so.2.2.0(event_process_active_single_queue.isra.33+0x446)
[    0x7f4fc871875f]: 
...python3.7/site-packages/p4p/../pvxslibs/lib/./libevent_core.so.2.2.0(event_base_loop+0x49f)
[    0x7f4fc8e21e00]: 
...python3.7/site-packages/p4p/../pvxslibs/lib/libpvxs.so.1.1(_ZN4pvxs4impl6evbase3Pvt3runEv+0x160)
[    0x7f4fc8b17f69]: 
...python3.7/site-packages/p4p/../epicscorelibs/lib/libCom.so.7.0.7.99.0(epicsThreadCallEntryPoint+0x69)
[    0x7f4fc8b038da]: 
...python3.7/site-packages/p4p/../epicscorelibs/lib/libCom.so.7.0.7.99.0(start_routine+0xda)
[    0x7f4fcb68bfa3]: 
/lib/x86_64-linux-gnu/libpthread.so.0(start_thread+0xf3)
[    0x7f4fcb3d306f]: /lib/x86_64-linux-gnu/libc.so.6(clone+0x3f)
2022-12-14 13:14:04 ConnP4P get IOC:m1.CNEN ret=Enable time=1.01
2022-12-14 13:14:04 011:47 01102 enabled=True
.2022-12-14 13:14:04 011:53 011999 teardown_class
2022-12-14 13:14:04 TestUtil close() begin
2022-12-14 13:14:04 TestUtil close() done