Re: SIGINFO/SIGUSR1 and SIGUSR2

[Guy Harris <gharris () sonic net>]

On Mar 28, 2024, at 2:19 PM, Denis Ovsienko <denis () ovsienko info> wrote:

> Yes, AIX and Haiku sometimes make portability issues manifest.

And, in this case, Solaris doesn't have SIGINFO, either; SunOS 0.x-4.x didn't have it, as BSD hadn't picked it up, and 
they didn't pass it along to be put into SVR4, so it's not in the SVR4-based SunOS 5.x.

As noted, neither does Linux.

I.e., at this point, if it's not named "somethingBSD" or "Mac OS X/OS X/macOS", it doesn't have SIGINFO.

> Changing the compiled-in defaults would be one thing, and given how long
> ago the current behaviour was implemented, it would be best to think
> twice before changing it.  There are users with learned keystrokes and
> scripts that work, let's keep it this way when possible.

The only change I'm suggesting to the compiled-in defaults is to change the default for SIGUSR1 from the current 
default of "print_stats if the system doesn't have SIGINFO, kill the process if it doesn't" to "print_stats regardless 
of whether the system has SIGINFO"; neither the default for SIGINFO (print_status if the system has it) nor the default 
for SIGUSR2 (flush_savefile) would be changed.

I don't see a way in which any remotely reasonable learned keystroke or script would depend on SIGUSR1 killing the 
process on *BSD/macOS, so I don't see an issue with SIGINFO *and* SIGUSR1 both causing stats to be printed.

> Allowing to override the defaults at run time

Which is what I was talking about there.
_______________________________________________
tcpdump-workers mailing list -- tcpdump-workers () lists tcpdump org
To unsubscribe send an email to tcpdump-workers-leave () lists tcpdump org
%(web_page_url)slistinfo%(cgiext)s/%(_internal_name)s