Defining TEVENT_NUM_SIGNALS as (2 * SIGRTMIN) so that SIGNAL-based AIO handling on FreeBSD works

[Jeremy Allison]

On Fri, Nov 30, 2012 at 03:06:18PM -0800, Richard Sharpe wrote:
> Hi folks,
> 
> I am canvassing opinions on whether there is a better way to do this.
> 
> Currently, the default AIO stuff in Samba does not work on FreeBSD
> because TEVENT_NUM_SIGNALS is set to 64 and there is a check to see
> that the signal number used by the AIO stuff does not exceed this
> number.
> 
> However, if RT_SIGNAL_AIO Is not set, then:
> 
> /* The signal we'll use to signify aio done. */
> #ifndef RT_SIGNAL_AIO
> #define RT_SIGNAL_AIO   (SIGRTMIN+3)
> #endif
> 
> in source3/smbd/aio.c but on FreeBSD
> 
> /usr/include/sys/signal.h:#define       SIGRTMIN        65
> 
> So, things do not work.
> 
> One solution is to define TEVENT_NUM_SIGNALS as 2 * SIGRTMIN ...
> 
> On Linux SIGRTMIN is 32.
> 
> Can anyone suggest a better fix?

Took a quick look at this and at least on Linux there's

#define SIGRTMAX

which looks like it might be part of the POSIX-RT standard.

Is this defined on *BSD ? If so, what is it defined to ?

Jeremy