Alfred Perlstein <bri...@rush.net> writes:
> This looks like what you are doing is trying to grab the data on the
> stack before "log" which is the return address.

Yes. It actually works :)

>                                                  I doubt this is
> at all portable and may fail because of optimizations and ABI, such
> as archs that store the return address in a register...

I know - I don't expect it to be portable.

> gdb and glibc have some functions to assist in runtime backtraces,
> perhaps a look there may help?

I found out about __builtin_return_address(0).

> > BTW, is dladdr() signal-safe?
> not according to the sigaction man page.

OK, is there any way I can find out that I am being called from a
signal handler, other than using a global variable? I want my logging
functions to be signal-safe - that's why I use writev(), and I've gone
to great lengths to ensure that log_makedate() (which uses
localtime_r() and strftime() to build a date string) and lvformat() (a
printf() clone with some additional goodies) are signal-safe.

DES
-- 
Dag-Erling Smorgrav - d...@flood.ping.uio.no


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