version.c

Advanced UNIX Programming is the long-awaited (19 years!) update to the 1985 original. Maybe "update

   if ((val == -1) && (errno))
   {
     printf("Bad option _SC_VERSION\n");
   }
   else if ((val == -1) && (!errno))
   {
     printf("POSIX.1 VERSION not Supported.\n");
   }
   else
   {
     printf("POSIX.1 VERSION Supported.\n");
   }

   val=sysconf(_SC_ARG_MAX);
   if (val == -1)
   {
     printf("Bad option _SC_ARG_MAX\n");
   }
   else
   {
     printf("POSIX.1 ARG MAX Value=%ld.\n",val);
   }
   val=sysconf(_SC_CHILD_MAX);
   if (val == -1)
   {
     printf("Bad option _SC_CHILD_MAX\n");
   }
   else
   {
     printf("POSIX.1 CHILD MAX Value=%ld.\n",val);
   }
   val=sysconf(_SC_CLK_TCK);
   if (val == -1)
   {
     printf("Bad option _SC_CLK_TCK\n");
   }
   else
   {
     printf("POSIX.1 CLK TCK Value=%ld.\n",val);
   }
   val=sysconf(_SC_NGROUPS_MAX);
   if (val == -1)
   {
     printf("Bad option _SC_NGROUPS_MAX\n");
   }
   else
   {
     printf("POSIX.1 NGROUPS MAX Value=%ld.\n",val);
   }
   val=sysconf(_SC_OPEN_MAX);
   if (val == -1)
   {
     printf("Bad option _SC_OPEN_MAX\n");
   }
   else
   {
     printf("POSIX.1 OPEN MAX Value=%ld.\n",val);
   }
   val=sysconf(_SC_STREAM_MAX);
   if (val == -1)
   {
     printf("Bad option _SC_STREAM_MAX\n");
   }
   else
   {
     printf("POSIX.1 STREAM MAX Value=%ld.\n",val);
   }
   val=sysconf(_SC_TZNAME_MAX);
   if (val == -1)
   {
     printf("Bad option _SC_TZNAME_MAX\n");
   }
   else
   {
     printf("POSIX.1 TZNAME MAX Value=%ld.\n",val);
   }


   errno=0;
   val=sysconf(_SC_ASYNCHRONOUS_IO);
   if ((val == -1) && (errno))
   {
     printf("Bad option _SC_ASYNCHRONOUS_IO\n");
   }
   else if ((val == -1) && (!errno))
   {
     printf("POSIX.4 ASYNCHRONOUS IO not Supported.\n");
   }
   else
   {
     printf("POSIX.4 ASYNCHRONOUS IO Supported.\n");
   }
   errno=0;
   val=sysconf(_SC_MAPPED_FILES);
   if ((val == -1) && (errno))
   {
     printf("Bad option _SC_MAPPED_FILES\n");
   }
   else if ((val == -1) && (!errno))
   {
     printf("POSIX.4 MAPPED FILES not Supported.\n");
   }
   else
   {
     printf("POSIX.4 MAPPED FILES Supported.\n");
   }
   errno=0;
   val=sysconf(_SC_MEMLOCK_RANGE);
   if ((val == -1) && (errno))
   {
     printf("Bad option _SC_MEMLOCK_RANGE\n");
   }
   else if ((val == -1) && (!errno))
   {
     printf("POSIX.4 MEMLOCK RANGE not Supported.\n");
   }
   else
   {
     printf("POSIX.4 MEMLOCK RANGE Supported.\n");
   }
   errno=0;
   val=sysconf(_SC_MEMORY_PROTECTION);
   if ((val == -1) && (errno))
   {
     printf("Bad option _SC_MEMORY_PROTECTION\n");
   }
   else if ((val == -1) && (!errno))
   {
     printf("POSIX.4 MEMORY PROTECTION not Supported.\n");
   }
   else
   {
     printf("POSIX.4 MEMORY PROTECTION Supported.\n");
   }
   errno=0;
   val=sysconf(_SC_MESSAGE_PASSING);
   if ((val == -1) && (errno))
   {
     printf("Bad option _SC_MESSAGE_PASSING\n");
   }
   else if ((val == -1) && (!errno))
   {
     printf("POSIX.4 MESSAGE PASSING not Supported.\n");
   }
   else
   {
     printf("POSIX.4 MESSAGE PASSING Supported.\n");
   }
   errno=0;
   val=sysconf(_SC_PRIORITIZED_IO);
   if ((val == -1) && (errno))
   {
     printf("Bad option _SC_PRIORITIZED_IO\n");
   }
   else if ((val == -1) && (!errno))
   {
     printf("POSIX.4 PRIORITIZED IO not Supported.\n");
   }
   else
   {
     printf("POSIX.4 PRIORITIZED IO Supported.\n");
   }
   errno=0;
   val=sysconf(_SC_PRIORITY_SCHEDULING);
   if ((val == -1) && (errno))
   {
     printf("Bad option _SC_PRIORITY_SCHEDULING\n");
   }
   else if ((val == -1) && (!errno))
   {
     printf("POSIX.4 PRIORITY SCHEDULING not Supported.\n");
   }
   else
   {
     printf("POSIX.4 PRIORITY SCHEDULING Supported.\n");
   }
   errno=0;
   val=sysconf(_SC_REALTIME_SIGNALS);
   if ((val == -1) && (errno))
   {
     printf("Bad option _SC_REALTIME_SIGNALS\n");
   }
   else if ((val == -1) && (!errno))
   {
     printf("POSIX.4 REALTIME SIGNALS not Supported.\n");
   }
   else
   {
     printf("POSIX.4 REALTIME SIGNALS Supported.\n");
   }
   errno=0;
   val=sysconf(_SC_SEMAPHORES);
   if ((val == -1) && (errno))
   {
     printf("Bad option _SC_SEMAPHORES\n");
   }
   else if ((val == -1) && (!errno))
   {
     printf("POSIX.4 SEMAPHORES not Supported.\n");
   }
   else
   {
     printf("POSIX.4 SEMAPHORES Supported.\n");
   }
   errno=0;
   val=sysconf(_SC_FSYNC);
   if ((val == -1) && (errno))
   {
     printf("Bad option _SC_FSYNC\n");
   }
   else if ((val == -1) && (!errno))
   {
     printf("POSIX.4 FSYNC not Supported.\n");
   }
   else
   {
     printf("POSIX.4 FSYNC Supported.\n");
   }
  errno=0;
   val=sysconf(_SC_SHARED_MEMORY_OBJECTS);
   if ((val == -1) && (errno))
   {
     printf("Bad option _SC_SHARED_MEMORY_OBJECTS\n");
   }
   else if ((val == -1) && (!errno))
   {
     printf("POSIX.4 SHARED_MEMORY_OBJECTS not Supported.\n");
   }
   else
   {
     printf("POSIX.4 SHARED_MEMORY_OBJECTS Supported.\n");
   }
  errno=0;
   val=sysconf(_SC_SYNCHRONIZED_IO);
   if ((val == -1) && (errno))
   {
     printf("Bad option _SC_SYNCHRONIZED_IO\n");
   }
   else if ((val == -1) && (!errno))
   {
     printf("POSIX.4 SYNCHRONIZED IO not Supported.\n");
   }
   else
   {
     printf("POSIX.4 SYNCHRONIZED IO Supported.\n");
   }
  errno=0;
   val=sysconf(_SC_TIMERS);
   if ((val == -1) && (errno))
   {
     printf("Bad option _SC_TIMERS\n");
   }
   else if ((val == -1) && (!errno))
   {
     printf("POSIX.4 TIMERS not Supported.\n");
   }
   else
   {
     printf("POSIX.4 TIMERS Supported.\n");
   }

   val=sysconf(_SC_AIO_LISTIO_MAX);
   if (val == -1)
   {
     printf("Bad option _SC_AIO_LISTIO_MAX\n");
   }
   else
   {
     printf("POSIX.4 AIO LISTIO MAX Value=%ld.\n",val);
   }
   val=sysconf(_SC_AIO_MAX);
   if (val == -1)
   {
     printf("Bad option _SC_AIO_MAX\n");
   }
   else
   {
     printf("POSIX.4 AIO MAX Value=%ld.\n",val);
   }
   val=sysconf(_SC_AIO_PRIO_DELTA_MAX);
   if (val == -1)
   {
     printf("Bad option _SC_AIO_PRIO_DELTA_MAX\n");
   }
   else
   {
     printf("POSIX.4 AIO PRIO DELTA MAX Value=%ld.\n",val);
   }
   val=sysconf(_SC_DELAYTIMER_MAX);
   if (val == -1)
   {
     printf("Bad option _SC_DELAYTIMER_MAX\n");
   }
   else
   {
     printf("POSIX.4 DELAYTIMER MAX Value=%ld.\n",val);
   }
   val=sysconf(_SC_MQ_OPEN_MAX);
   if (val == -1)
   {
     printf("Bad option _SC_MQ_OPEN_MAX\n");
   }
   else
   {
     printf("POSIX.4 MQ OPEN MAX Value=%ld.\n",val);
   }
   val=sysconf(_SC_MQ_PRIO_MAX);
   if (val == -1)
   {
     printf("Bad option _SC_MQ_PRIO_MAX\n");
   }
   else
   {
     printf("POSIX.4 MQ PRIO MAX Value=%ld.\n",val);
   }
   val=sysconf(_SC_PAGESIZE);
   if (val == -1)
   {
     printf("Bad option _SC_PAGESIZE\n");
   }
   else
   {
     printf("POSIX.4 PAGESIZE Value=%ld.\n",val);
   }
   val=sysconf(_SC_RTSIG_MAX);
   if (val == -1)
   {
     printf("Bad option _SC_RTSIG_MAX\n");
   }
   else
   {
     printf("POSIX.4 RTSIG MAX Value=%ld.\n",val);
   }
   val=sysconf(_SC_SEM_NSEMS_MAX);
   if (val == -1)
   {
     printf("Bad option _SC_SEM_NSEMS_MAX\n");
   }
   else
   {
     printf("POSIX.4 SEM NSEMS MAX Value=%ld.\n",val);
   }
   val=sysconf(_SC_SEM_VALUE_MAX);
   if (val == -1)
   {
     printf("Bad option _SC_SEM_VALUE_MAX\n");
   }
   else
   {
     printf("POSIX.4 SEM VALUE MAX Value=%ld.\n",val);
   }
   val=sysconf(_SC_SIGQUEUE_MAX);
   if (val == -1)
   {
     printf("Bad option _SC_SIGQUEUE_MAX\n");
   }
   else
   {
     printf("POSIX.4 SIGQUEUE MAX Value=%ld.\n",val);
   }
   val=sysconf(_SC_TIMER_MAX);
   if (val == -1)
   {
     printf("Bad option _SC_TIMER_MAX\n");
   }
   else
   {
     printf("POSIX.4 TIMER MAX Value=%ld.\n",val);
   }
	return 0; /* mjr */
}  /*end of main*/

#if 0
Other system limits
The "/usr/include/limits.h" file defines the various limits for the system such as SEM_NSEMS_MAX which is the maximum number of semaphores that one process can have open at a time. This file includes the following:

#ifdef	__USE_POSIX
/* POSIX adds things to <limits.h>.  */
# include <bits/posix1_lim.h>
#endif

#ifdef	__USE_POSIX2
# include <bits/posix2_lim.h>
#endif

#ifdef	__USE_XOPEN
# include <bits/xopen_lim.h<
#endif


Which means, the files "/usr/include/bits/posix1_lim.h" and "/usr/include/bits/posix2_lim.h" define the system limits.
#endif

#endif /* FREEBSD */