Ion Gaztanaga wrote:
Ok, I see. Detecting POSIX conformance is really a nightmare ;-) I think I should just check for _POSIX_SHARED_MEMORY_OBJECTS, because I don't want to miss native shared memory for systems that support it.
As far as I can see, Interprocess library uses the following _POSIX_* feature test macros: _POSIX_BARRIERS _POSIX_SEMAPHORES _POSIX_SHARED_MEMORY_OBJECTS _POSIX_THREAD_PROCESS_SHARED _POSIX_TIMEOUTS In theory, a check for these macros should be accompanied by the check of the value of _XOPEN_SOURCE feature test macro because different releases of X/Open Specs define these _POSIX_* feature test macros differently. Using _POSIX_SHARED_MEMORY_OBJECTS as an example, I'd suggest the following check: #if defined(_POSIX_SHARED_MEMORY_OBJECTS) # if !((_XOPEN_SOURCE >= 600) && (_POSIX_SHARED_MEMORY_OBJECTS - 0 <= 0)) # define BOOST_INTERPROCESS_POSIX_SHARED_MEMORY_OBJECTS # endif #endif I verified that the check above works in a default compilation on Linux, Tru64 and HP-UX, i.e. BOOST_INTERPROCESS_POSIX_SHARED_MEMORY_OBJECTS macro gets defined. VMS supports shared memory objects but it does not define _POSIX_SHARED_MEMORY_OBJECTS macro, so you can define BOOST_INTERPROCESS_POSIX_SHARED_MEMORY_OBJECTS on VMS as the following (70200000 is the first version of libc on VMS having shm_*() functions): #if defined(__vms) # if __CRTL_VER >= 70200000 # define BOOST_INTERPROCESS_POSIX_SHARED_MEMORY_OBJECTS # endif #endif Currently, VMS does not support other _POSIX_* features used by the Interprocess library, so, BOOST_INTERPROCESS_POSIX_SHARED_MEMORY_OBJECTS should be the only macro defined on this platform.
I suppose I have the same problem for other posix features like _POSIX_THREAD_PROCESS_SHARED. So if I understand it correctly, checking only for the existence of option macros should be enough if I want to support SUSV2 systems, right?
Right, but, I think, you also want to support XPG6 systems where the feature test macro can be defined with a value of -1 or 0. The check above takes it into account. Thanks, Boris