determine whether code is running in a signal handler context

[Florian Weimer]

On 11/27/2017 01:50 PM, Yubin Ruan wrote:
> 2017-11-27 19:55 GMT+08:00 Florian Weimer <fweimer@redhat.com>:
>> On 11/27/2017 09:42 AM, Yubin Ruan wrote:
>>>
>>> Still remember this thread? It turn out that determining whether or not
>>> you
>>> are currently in a signal handler is trivial with libunwind:
>>
>>
>> This is incorrect.  libunwind (or any other unwinder) relies on information
>> which is not always available.
> 
> what information?

Unwind tables.  A correct stack pointer or frame pointer.

Florian