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I created a python code following this description:

import os
import time
import signal

def receiveSignal(signalNumber, frame):
 print('Received:', signalNumber)
 return

signal.signal(signal.SIGUSR1, receiveSignal)

# output current process id
print('My PID is:', os.getpid())

# wait in an endless loop for signals
while True:
 print('Waiting...')
 time.sleep(3)

which runs fine. But when I try to send a SIGUSR1 signal from another terminal, e.g. :

kill -10 55947

the python code fails as follows:

My PID is: 55947
Waiting...
Waiting...
Bus error: 10

The code is running on MacOS 10.13.6, and I tried using python 2.7.12 and python 3.6.2. In both cases I get that Bus Error.

Is there a way to fix that? Maybe this is a mac issue? I expect the running code to execute the method receiveSignal, but otherwise stay in the shile loop.

I think, the problem is, in MacOS, the SIGNAL 10 means SIGBUS.

See the signal list https://developer.apple.com/library/archive/documentation/System/Conceptual/ManPages_iPhoneOS/man3/signal.3.html

See the signal details,

 1 SIGHUP terminate process terminal line hangup
 2 SIGINT terminate process interrupt program
 3 SIGQUIT create core image quit program
 4 SIGILL create core image illegal instruction
 5 SIGTRAP create core image trace trap
 6 SIGABRT create core image abort program (formerly SIGIOT)
 7 SIGEMT create core image emulate instruction executed
 8 SIGFPE create core image floating-point exception
 9 SIGKILL terminate process kill program
 10 SIGBUS create core image bus error
 ...
 ...
 30 SIGUSR1 terminate process User defined signal 1
 31 SIGUSR2 terminate process User defined signal 2

Hence, the error.

Try sending SIGNAL 30, and see :)