Realtime signals supported?


sysconf() with _SC_REALTIME_SIGNALS reports invalid argument, although
_SC_REALTIME_SIGNALS is defined (obviously, otherwise the example
wouldn’t compile). Are realtime signals supported (SIGRTMIN through
SIGRTMAX)? In spite of the sysconf() result, they appear to work OK,
but I’d rather be sure… Environment: The current QNX Momentics NC.

Btw, is there a clear statement available somewhere as to which
``options’’ of POSIX (which now appears to be incorporated in IEEE Std
1003.1-2001 (SUSv3)) are supported? I couldn’t find anything in the
online documentation.

In case there might be a bug in my example, here is the source:

#define _POSIX_C_SOURCE 199506


#include // for perror

#include <unistd.h>
#include <signal.h>

void die( char const* msg ) {
std::perror( msg ) ;
std::exit( 1 ) ;

int main() {
errno = 0 ;
long const i = ::sysconf( _SC_REALTIME_SIGNALS ) ;
if( errno ) { die( “sysconf” ) ; }

if( i <= 0 ) {
std::cerr << “realtime signals not supported\n” ;
std::exit( 1 ) ;