EVMS on Linux uses heartbeat's cluster plumbing base64
functions to encode and decode binary data for sending
over the wire. A zero-length message, like one passed
for EVMS_CLOSE_ENGINE, gets encoded as a single 't'
Because base64 encoding must be a multiple of 4 in
length, the base64_to_binary() call on the remote end
fails and returns -1, which gets promptly stored as the
unsigned message length. A subsequent call to
log_message() then causes a segmentation violation
when it tries to read the entire length of virtual memory
from 0 - 0xffffffff.
There are many other zero-length messages generated
by engine/remote.c. I assume they would all fail in the