A successful parse of EPICS_CA_CONN_TMO stored the value into connTMO
unchecked, so EPICS_CA_CONN_TMO=-5 or =0 left the connection-verify
watchdog deadline permanently in the past. The watchdog then fires
continuously, flooding stderr with "Virtual circuit unresponsive" and
pinning a CPU while updates still arrive. NaN and inf (which
epicsScanDouble also accepts) slip past any ordering comparison: a NaN
period leaves the watchdog deadline arithmetic undefined, and an
infinite period silently disables circuit verification.
Fold the validity check into the existing parse-failure branch, so an
unparsable, non-finite, or non-positive value takes the same path:
warn once and fall back to the 30 s CA_CONN_VERIFY_PERIOD default.
This mirrors the sibling EPICS_CA_MAX_ARRAY_BYTES handling a few lines
below, which already gates a parse failure and an out-of-range value
in one condition, and matches the finite() gate on
EPICS_CA_MAX_SEARCH_PERIOD in udpiiu.cpp.
Sang Woo Kim
a8180003e9